A Liberal Democrat MP issued a written undertaking tonight that he would not repeat a reference to "the Jews", which caused outrage last week.
David Ward was formally censured by Lib Dem chief whip Alistair Carmichael after he said he was "saddened that the Jews, who suffered unbelievable levels of persecution during the Holocaust, could within a few years of liberation from the death camps be inflicting atrocities on Palestinians in the new state of Israel and continue to do so on a daily basis".
The Bradford East MP, who initially defended his words, apologised yesterday for any "unintended offence" caused by a message posted on his website ahead of Holocaust Memorial Day.
After a meeting with Mr Carmichael this evening, the chief whip issued a letter saying: "I am strongly of the view that your use of the phrase 'the Jews' in this context was unacceptable and I formally censure you for that.
"In line with our conversation, and notwithstanding the strength with which you hold your views on the situation in the Middle East, I would be grateful if you would confirm the undertaking that you gave to me in our meeting that you will not again use the phrase 'the Jews' in this context."
Responding, Mr Ward wrote: "I confirm that I am prepared to give you the undertaking that you asked for in our meeting."
His controversial remarks were made in a website posting after signing a Holocaust memorial book.
Amid a furious backlash and a complaint from the Holocaust Educational Trust, he appeared on television to defend the comments and reinforce his point.
But in a new post yesterday he said he "never for a moment intended to criticise or offend the Jewish people as a whole, either as a race or as a people of faith, and apologise sincerely for the unintended offence which my words caused".
He added: "I recognise of course the deep sensitivities of these issues at all times, and particularly on occasions of commemoration such as this weekend."
He insisted however that he would "continue to make criticisms of actions in Palestine in the strongest possible terms for as long as Israel continues to oppress the Palestinian people".
Organisers of a memorial day for victims of the Holocaust yesterday "utterly condemned" Mr Ward.