The historic referendum on whether Britain stays or leaves the European Union will take place on Thursday June 23, David Cameron has confirmed.
After a tense Cabinet meeting, the Prime Minister emerged into Downing Street to announce the date of the poll that will decide if Britons want to go it alone for the first time in 40 years.
The referendum will take place at the height of summer, on the first day of the Glastonbury music festival and during the European football championships.
With the world’s media looking on, and under typically British rainy grey skies, Mr Cameron fired the starting gun in the race for Britain’s future as he declared that the country would be better off in the EU.
Using all the trappings of office, he spoke at a podium outside the famous black door of No10 to claim that his hard-won reform deal in Brussels would ensure the UK had "special status" to protect it from European integration and the eurozone.
David Cameron in Downing Street
"I don't love Brussels, I love Britain," Mr Cameron said. But he warned that quitting the EU would be a "leap in the dark". "I believe Britain will be safer, stronger and better off by remaining in this reformed European Union."
The two-hour Cabinet meeting, the first to take place on a Saturday since the Falklands War in 1982, exposed the deep divisions within the Tory party that have dogged it ever since rebel MPs voted against the Maastricht Treaty that tied the EU closer together.
In a bid to avoid even deeper splits, Mr Cameron lifted ministerial ‘collective responsibility’ to allow Cabinet colleagues to campaign openly for ‘Brexit’ for the first time.
Boris Johnson, leaving No.10 last week
However, one of the biggest players in the drama, Boris Johnson, remained silent, and HuffPost UK understands he will make his position clear on Sunday, after Mr Cameron unveils new plans to defend British Parliamentary ‘sovereignty’ over EU law.
A recent IpsosMORI poll found that the Mayor of London was the one politician who could swing the referendum, adding upto 15% to the Brexit campaign.
The last time a Cabinet was permitted to fight on different sides was during the 1975 referendum on whether the UK should stay in Europe’s trading bloc.
Justice Secretary Michael Gove, Commons Leader Chris Grayling and Work and Pensions Secretary Iain Duncan Smith were set to announce they wanted Britain to quit the EU.
But in a blow to the Brexit camp, Business Secretary Sajid Javid opted to back the 'Remain' camp.
And Home Secretary Theresa May finally confirmed she would back the In campaign too.
With national security and crime set to be a key feature of the ‘Remain’ campaign, Mrs May said “for reasons of security, protection against crime and terrorism, trade with Europe, and access to markets around the world - it is in the national interest to remain a member of the European Union”.
Mr Cameron and Chancellor George Osborne both stressed that Britain would be better off economically if it kept the free-trade links with the 300 million residents in the EU, warning Brexit would be a "leap into the dark".
Labour leader Jeremy Corbyn said the PM's Brussels reform deal - which will curb migrant benefits for seven years and protect the City of London - was "a sideshow" and "largely irrelevant" to the problems most British people face.
But with Labour overwhelmingly in favour of staying in the EU, he added: "We will be campaigning to keep Britain in Europe in the coming referendum, regardless of David Cameron’s tinkering, because it brings investment, jobs and protection for British workers and consumers."
If Boris decides to call for the UK to leave the EU, his chances of succeeding Mr Cameron as Tory party leader could be boosted hugely as many grassroots Conservatives have long wanted to sever our links with Brussels.
Yet the move is not without risk, especially if Britain votes to stay in the Union. And Mr Johnson would be on the same side as both Nigel Farage and George Galloway, whose arrival at a Brexit rally last night prompted a walk-out by supporters.
If Mr Cameron loses the referendum - and polls have given both the In and Out camps the lead in recent weeks - he is sure to face calls to quit as Prime Minister, give how much he has put his personal and political credibility on the line.
For many of the public, the June 23 poll will take place as they are distracted by more popular attractions such as watching the European football championships or the start of the Glastonbury festival.
Around 135,000 Glastonbury revellers may miss out on the chance to cast their ballot in the referendum because there will be no polling station at the festival.
The Electoral Commission has said it would not be legally possible for a polling station to be set-up at Glastonbury for people to vote in person and they will have to vote in their local areas.
In the Euro championships, the group stages will have been completed by Thursday, June 23. England, Wales and Northern Ireland will know by then if they have been forced out of Europe - at least in a footballing sense.