Respect's George Galloway today denied claims he had converted to Islam at a secret ceremony more than a decade ago.
The maverick MP took part in the "shahadah" conversion ceremony, attended by members of the Muslim Association of Great Britain, at a hotel in Kilburn, London, it was reported today.
Jemima Khan, who converted to Islam ahead of her marriage to cricketer Imran Khan, claimed in an article for the New Statesman she knew someone who had attended the event.
But the Bradford West MP, who has repeatedly refused to answer questions about his faith, dismissed it as "totally untrue".
Galloway went on to attack Khan's article on Twitter this afternoon
In the days ahead of his shock landslide by-election victory last month, a letter - which Galloway denies being behind - went out to voters highlighting his record of support for Palestine, his work for "the freedom of Kashmir" and his abstention from alcohol.
It added: "God knows who is a Muslim. And He knows who is not. Instinctively so do you."
Khan, who interviewed the MP in his new constituency, which has a large Muslim community, starts the article:
"George Galloway, MP for Bradford West, is a Muslim.
"He converted more than ten years ago in a ceremony at a hotel in Kilburn, north-west London, attended by members of the Muslim Association of Great Britain.
"Those close to him know this. The rest of the world, including his Muslim constituents, does not."
Khan tells Galloway she knows someone "who attended your shahadah" and says, "so you converted?"
According to the article he replied: "I can't answer that. God knows who is a Muslim."
When being sworn in as an MP Galloway chose to affirm, rather than make the pledge on a religious text.
He told Khan: "People ask me this, why did I affirm in Parliament when I swore in?
"The answer is: I had to take an oath of allegiance in which I don't believe, to the Queen and all her heirs and successors, and I have no allegiance to any of them, and I could not possibly swear such a thing on a holy book. So nothing else should be read into the affirmation."
Galloway claimed today the article was littered with "deliberate falsehoods" and "schoolgirl howlers".
In a statement he added: "The opening paragraph of Jemima Khan's piece in the New Statesman, referring to an alleged conversion ceremony, is totally untrue.
"Moreover I told her it was fallacious when she put it to me. I have never attended any such ceremony in Kilburn, Karachi or Kathmandu.
"It is simply and categorically untrue."