Disgraced Labour grandee Ken Livingstone has insisted his claim that Hitler was a Zionist “before he went mad and killed six million Jews” was not anti-Semitic.

The former London mayor – suspended by his party last month – made the bizarre offer of a “free meal out” for anyone who can prove his provocative statements on Hitler’s supposed support for Zionism wrong.

The comments, made in a BBC interview in the wake of Bradford West MP Naz Shah’s suspension, were debunked by experts as “categorically false”.

But Livingstone – who in 2006 was suspended from the mayoralty after comparing a Jewish journalist to a concentration camp guard – maintains that he was right.

Speaking on Talk Radio, the veteran left-winger blamed “embittered old Blairite MPs” for the media storm his outburst provoked.

He said: “There’s this interesting accusation I’m anti-Semitic. Not a single newspaper, or radio, or TV programme has produced any evidence in the past two weeks that what I said was wrong.

“I’ll offer a free meal out for anyone who can prove what I said was wrong. I was asked a question about Hitler’s policies and I dealt with it in about 40 words and moved on.”

Livingstone was branded a “Nazi apologist” by campaigning Labour MP John Mann in the wake of the now notorious Daily Politics interview.

And despite claiming not to “want to drag this out forever”, the unrepentant septuagenarian has since refused to apologise in a series of calamitous media appearances.