He believes the European Union was conceived by Nazi Germany, suggests the Bilderberg Group is a "shadow world government", and wants to ban the building of new mosques.
Meet Gerard Batten, senior Ukip MEP and top lieutenant to Nigel Farage.
In recent weeks, Farage has tried to dismiss the string of "unpleasant" and "appalling" remarks - to quote the Prime Minister - made by various Ukip candidates by stressing how minor they are within the party. Batten, thus, poses a particular problem for his party leader.
A founding member of Ukip in 1993, he has been the party's chief whip in the European Parliament since 2009 after being appointed by Farage to the post. Batten was also Ukip's mayoral candidate in London in 2008 and came second in the party's leadership election in 2009.
Yet the London MEP, first elected in 2004 and re-elected in 2009, has a wide range of controversial opinions, as colourful as the pink suits he is known to wear.
"Gerard is much more hardline than many of his colleagues in the party," a party insider says. "He's got very strong views, with many of them too strong for a lot of people."
HuffPost UK spoke to a dozen sources, including current and former colleagues of Batten, both on and off the record, to find out more about the controversial top Ukipper.
'IT'S NOT LIKE HE WANTS TO KILL ALL MUSLIMS'
Batten, the party's "immigration and Islamism" spokesman, hit the headlines in February when he said he still agreed with a "charter of Muslim understanding" that he had originally proposed in 2006. British Muslims, according to Batten's document, were meant to sign as a "code of conduct" which would signify that they rejected violence and accepted equality.
The MEP also argued that some Muslim texts also required updating, particularly those bits he claimed say "kill Jews wherever you find them". He said: "If they say they cannot revise their thinking on those issues, then who's got the problem – us or them?"
Batten has previously suggested banning halal and kosher slaughter of animals as well as outlawing the legal recognition of Islamic banking in the UK. Speaking in 2010, Batten pledged to end the building of new mosques in the UK, until and unless a non-Muslim place of worship was built in Mecca. (Batten insists on referring to Wahhabi-run Saudi Arabia as the "heartland" of Islam.)
Ex-Ukip MEP Nikki Sinclaire, who joined the party in the 1990s, calls her former colleague an "incredibly paranoid person".
"Gerard talks about the gradual takeover by the Muslims of Great Britain and sharia law. He has been hell-bent on attacking Muslims."
Sinclaire claims that Batten is "very good friends" with far-right European politicians like Dutch MP Geert Wilders and Belgium's Vlaams Belang, adding: "I often see him in the parliament with those MEPs."
Although, Farage and Ukip have rejected joining up with far-right parties led by the likes of Wilders (in Holland) and Marine Le Pen (in France) at a Europe-wide level, Batten nonetheless invited Wilders to the European Parliament in December 2008 to screen his controversial film 'Fitna' to MEPs, praising him as "a brave man trying to defend western civilisation".
Gerard Batten with Geert Wilders at a press conference in 2008
The 17-minute film, featuring shocking imagery of the attacks on New York in 2001 and Madrid in 2004 combined with quotes from the Quran, Islam's holy book, was called 'offensively anti-Islamic' by UN Secretary General Ban Ki-moon. Wilders has called for a ban on the Quran and claims "there is no such thing as 'moderate Islam'".
Batten, however, seized upon the decision by the UK government in 2009 to ban Wilders from entering the country to show his film in the House of Lords, branding it "appeasement" to a "dark age ideology" that stopped the "free movement of ideas".
One party insider admits that Batten has very "strong" views about Islam, quipping: "It's not like he wants to kill all Muslims."
Simon Cressy, from the anti-racism group Hope Not Hate, describes Batten as "on the far right of Ukip", adding: "He's very senior. People like him prove the reality about Ukip when they insist they're not racist and Islamophobic.
"He has got lots of links to various anti-Islamic group over the past few years, he has spoken at meetings where there has been various sorts of dodgy-anti islamic politicians."
Batten addressed the inaugural 'Counter Jihad' conference in Brussels on 18 October 2007, which featured Robert Spencer, author of 'Religion of Peace, Why Christianity is and Islam Isn’t', as its keynote speaker. Spencer was banned by home secretary Theresa May from entering Britain, after planning to speak at an English Defence League (EDL) rally in Woolwich. The Home Office said US author had been banned for making anti-Muslim statements which may "foster hatred" and lead to "inter-community violence" in the UK.
Batten has himself made contact with the English Defence League, admitting to meeting EDL funder Alan Lake in 2011 as he wanted to find out more about the "phenomenon".
He explained: "Mr Lake gave me his assurances that the EDL were a non-racist, non-violent organisation and that is only concerned with combating the ideology of extremist and fundamentalist Islamism and had no prejudice against Muslims as such."
For Muslim imam and activist Ajmal Masroor, Batten's presence in the top tier of Ukip proves it is not "a political party that is fit to serve the 21st century multicultural and multi-faith Europe". Masroor, a former Liberal Democrat parliamentary candidate, accuses the Ukip immigration spokesman of "espousing outright discrimination" and "spreading hate".
Batten's political opponents agree. "I find his past association with far-right extremism, no matter how much he tries to deny it now, totally reprehensible. It exposes the close relationship between Ukip on the hard-right and extremist parties," says Labour MEP Richard Howitt, who calls Batten "boorish" and "slightly aggressive".
The Tory MEP Sajjad Karim, who is a Muslim himself and vice-president of the European Parliament's anti-racism group, compares Batten's views on Muslims to the Nazi treatment of the Jews. "The vast majority of Britons find his views on Muslims repugnant and reminiscent of another era where a whole religious community was stigmatised and targeted in this very same way," he told HuffPost UK.
However, a Ukip insider dismissed Howitt and Karim's Howitt's remarks as "hyperbolic nonsense", adding: "Has Mr Karim never heard of Godwin's law? Well, you lose."
The source added that Batten "may come across as obsessive" because he is "single-minded", but that he "very hard-working, utterly committed to the cause of Britain leaving the EU."
'IMMIGRATION? HE IS TO THE RIGHT OF UKIP'
It isn't just Muslims who have been targeted by the Ukip immigration spokesman. Batten wrote a provocative paper for Ukip in 2010 titled "Immigration - Action Overdue!" which laid out his thoughts at length on the effect of immigrants on Britain.
He claimed that "the English will become a minority in their own land", warning that most Brits "within a few decades" would be "immigrants, or the children and grandchildren of immigrants".
While Farage squirms about what he meant when linking Romanians with criminality, Batten does not beat around the bush, writing: "Apparently Romanians are cornering the market in hole-in-the-wall-fraud."
Batten also warns that many parts of Britain are now "more like enclaves of Pakistan, Bengal or India than English cities", blaming the "phenomenon of 'White flight'".
Former Ukip deputy leader Mike Nattrass MEP, who was a member of the party until 2013, said Batten was "to the right of me and other people in the party" on immigration, but added: "He thinks and believes what he says. As an Englishman, he perfectly has the right to say what he thinks."
Former party leader Dr Alan Sked, who founded Ukip in 1993 alongside Batten, said he was surprised by the latter's hardline stance on immigration as the Ukip MEP's wife is from the Philippines.
Sked, an international history professor at the London School of Economics, has previously caused controversy for suggesting he had heard Farage use racial slurs in his presence - but the former party leader has a much rosier verdict of Batten.
"He was always hard working and had a good sense of humour. I never heard him say anything extreme in my time."
'THE SHADOW WORLD GOVERNMENT'
Batten has gained particular renown for campaigning about the Bilderberg Group, which hosts an annual conference discussing international issues which is attended by world leaders and business chiefs. For conspiracy theorists, these secretive gatherings have long been used by unnamed 'elites' to further their nefarious, global agendas.
As protesters gathered outside 2013's meeting at the Grove Hotel in Watford, Batten was on hand to give an interview to US radio shock jock and 9/11 'truther' Alex Jones about the Bilderberg "conspiracy".
Batten told Jones he had regularly been writing to politicians to ask them why they attended the conference and who paid for them, saying: "If you are really here to talk about things in the public interest, who do you think you can do it in secrecy? Why not in public?"
Asked if he thought it was a "conspiracy", he responded: "What's the definition of a conspiracy? It's two or more people meeting in secret to achieve an end which may be illegal or legal. In the strictest use of the word, it is a conspiracy.
"The bigger conspiracy has been the fact that the media hasn't spoken about this for 59 years and haven't allowed it to go on without any reporting."
He also said: "Look who owns the media, it is owned by powerful people and they go to powerful meetings like this."
Batten's focus on media ownership draws concern from Jewish groups for its undertones. Mark Gardner, from the Community Security Trust (CST), told HuffPost UK: “Gerard Batten stresses that he does not believe the more extreme conspiracy theories about the Bilderberg Group, but any notions of secret political and media power can risk echoing well-worn anti-Semitic ideas.”
Proving he is no stranger to conspiracy theories, Batten suggested to Jones that the European Union had been originally proposed by the Nazis, pointing to a plan by high-ranking Nazi official Dr Walter Funk in 1942 that sketched out "how are we going to run the economy after we have won the war".
The Ukip chief whip also claimed that in 1975, when the UK was debating whether to stay in the European Union, the CIA funnelled money into the Yes campaign and the BBC "had meetings to ensure the Yes vote was delivered."
Batten described the alleged CIA involvement as an "instrument of American foreign policy at the time" and complained that "the No vote was totally outspent and outclassed" by US intelligence.
He told other reporters: "[Bilderberg] has been called a 'shadow world government', whether that's true or not, I don't know, but nobody else does either."
Cressy, from Hope not Hate, says: "People see Gerard as being an anti-Bilderberg campaigner and this anti-establishment guy, when he's not really. He's like the embarrassing uncle you don't want to talk about."
Former colleagues, such as ex-Ukip deputy leader Nattrass, look at Batten's obsession with Bilderberg with bemusement. "There's always someone who turns up at hustings and goes on about Bilderberg - it's like going after the freemasons."
Ex-Ukip MEP Sinclaire recalls attending leadership hustings alongside Batten in 2009: "We did several hustings and he would talk about Bilderberg and all these kind of things – and you’d think, 'Really?'"
A Ukip insider played down Batten's interest in Bilderberg, saying: "Gerard has his own side-interests as everybody does in politics. They're not Nigel's but when it comes to the key issues, they're as one."
THE GREAT SURVIVOR
Having worked as a salesman at British Telecom for 28 years, Batten helped found Ukip and then rose up the ranks, eventually standing for the party leadership in 2009 and coming second to Lord Pearson.
Today, he is one of the most senior and high-profile members of Ukip - which has its downsides. Earlier this month, Batten reported that a brick was thrown through his living room window in the middle of the night.
His party leader was quick to offer his support and blamed the attack on "the media campaign against UK".
Relations, however, are said to be pretty poor between the two men. A well-placed Ukip insider said the pair "are not socially close and never have been", adding: "they're not drinking buddies".
HuffPost UK repeatedly contacted Farage and Batten for comment, but at the time of publishing, they have yet to respond.
Ex-Ukip MEP Godfrey Bloom says Batten is not "clubbable", but adds: "I've always found that what you see is what you get." Bloom declines to endorse Batten's more "out there" views on Islam and Muslims.
Sinclaire describes Batten as the "official controlled opposition" within Ukip to Farage, explaining: "Anyone who has ever questioned or stood up to Farage has basically been destroyed. Gerard Batten challenges Nigel and always survives. My belief is that he’s the one who Nigel puts up [with] and controls.
"I know him and Farage don’t get on. I question how he can survive in Ukip. They're not good friends. My only conclusion is that he controls him."
Gerard Batten and Nigel Farage
Nattrass says that Nigel "does not like" Batten and "has said some disgusting things about him before".
"Nigel tried to sideline him in the 2009 European elections and stop him being top of the candidates' list in London. Gerard is where he is because Nigel can control him. Anyone he can't control, he shoves out of the party."
Sked recalls Batten and Farage have been at odds for much longer, claiming that the London MEP even backed a vote to kick Farage out of Ukip back in 1997, but quit the party's national executive when "threatened with having to share the subsequent legal bills."
Batten left the party in 1998 in protest at Ukip's decision to change its position on sending its MEPs to Brussels, after previously having adopted a position of refusing to attend the European Parliament once they were elected to it.
"Nigel was one of the prime movers of the change at the party policy," a party insider recalls. "Gerard was dead set against the policy and wanting it to keep to its core values."
Batten's own core values are controversial, to say the least. His political opponents call him a supporter of the far right, and see him as an anti-Islam, anti-immigrant extremist. The fact that he is a believer in CIA and Nazi conspiracies don't help his credibility, either.
Speaking on BBC2's Newsnight on Monday, Farage told Jeremy Paxman: "We do run our own party... all those people who said offensive things will be booted out."
He might, therefore, need to have a word with his immigration spokesman.