Ken Livingstone said he regretted sparking a storm over anti-Semitism in the Labour Party but insisted it was a "nonsense" stirred by "embittered Blairites" to undermine Jeremy Corbyn.
Hours after the Opposition leader sought to put a lid on the row by announcing an independent investigation and a tightening of party rules, Mr Livingstone returned to the airwaves with another staunch defence of his contention that Hitler had been a Zionist.
The former mayor of London - a close ally of Mr Corbyn who was suspended by the party over the comments - said he was sorry if his views had upset Jewish people but that he had simply made a "statement of fact" that had been repeated two days before by Israeli premier Benjamin Netanyahu.
He said he was confident of being cleared to return to the party ranks after an investigation despite widespread calls for his expulsion, as there could be no evidence that he was anti-Semitic.
Former Liberty director Shami Chakrabarti has been appointed by Mr Corbyn to head a panel tasked with drawing up "a statement of principles and guidance about anti-Semitism and other forms of racism".
A strengthened code of conduct will "make explicitly clear for the first time that Labour will not tolerate any form of racism, including anti-Semitism, in the party" and provide guidance on acceptable language.
Mr Corbyn insists there is no "crisis" within the party but his handling of anti-Semitism allegations, which have led to the suspension of Mr Livingstone and Bradford West MP Naz Shah and several other party members, has been criticised.
Mr Livingstone told LBC: "I really regret saying it because it has caused all this disruption. I never regret saying something that is true.
"How can I have hurt and offended the Jewish community when the prime minister of Israel said exactly the same thing?"
He said he had had "quite a lot of texts and Tweets from Jewish people saying 'we would like to come along and support you at this inquiry'".
He said: "If you look at what this is all about, it's not about anti-Semitism in the Labour Party.
"What this is all about is actually the struggle of the embittered old Blairite MPs to try to get rid of Jeremy Corbyn."
He said Mr Corbyn was "clearly not very happy" with the situation but said he would "take a bullet" to keep him in power and would not do any further media interviews on the issue - after two days in and out of TV studios and being publicly attacked by Labour MP John Mann.
"I am not doing any more interviews because the Labour Party has got to get away from all this nonsense and back to getting the vote out on Thursday," he said.
"But the simple fact is that I did not create this problem; it was created by a bunch of embittered Blairite MPs who stirred up all this nonsense about anti-Semitists.
"The really appalling thing here is dishonest MPs who know that what I said is true have stirred up all this nonsense because they want to damage our chances at the local election so they then have a chance of undermining Jeremy.
"Now I don't think that is going to happen."