Alan Howarth, elected three years ago as the Conservative MP for Stratford- on-Avon, took his seat on the opposition benches yesterday to loud Labour cheers.
While in the Commons, he collected "probably 25" letters from Tory MPs, "not at all endorsing my decision, but people have been kind enough to respect my integrity", he said.
The symbolic moment of crossing the floor of the House - the first time an MP has gone from Tory to Labour - was timed to embarrass Michael Heseltine as he rose to take his first question time as Deputy Prime Minister.
But Mr Howarth later fluffed his first words from the Labour side, being rebuked by Michael Morris, a deputy speaker, for asking six questions instead of one when he intervened in the speech of Michael Portillo, Secretary of State for Defence, whose party conference speech "of extraordinary xenophobia and anti-foreigner prejudice" Mr Howarth said confirmed his decision to change parties.
Mr Portillo returned the insult by noting that Mr Howarth had become "no less verbose in his transition to the other side of the House". But he did not answer his question, about the dangers of British industry depending so heavily on arms exports.
Mr Howarth is the proud possessor of a Labour Party membership card, but is not yet technically a Labour MP, because he is waiting for his application to take the Labour whip to be approved. But he was warmly welcomed by all the Labour MPs he met.
Before his debut in the Commons, he had lunch as an honorary Labour MP, under the glare of the television camera lights, with Peter Snape and Dennis Turner, leaders of the West Midlands group of the Parliamentary Labour Party.
Mr Howarth then had to brave the photographers, the compliments of Labour MPs and mixed responses of Tories, as he entered the Palace of Westminster in the Labour interest. "I got up this morning and looked at the tabloids - they informed me I was going to have to run a gauntlet of hate. But it wasn't really like that," he said.
Mr Snape ushered his new colleague into the tea room, the MPs' inner sanctum, where he "crossed the room" rather than the floor by sitting at the Labour end near the door. "I have never been poured so many cups of tea," he said.
Other practical arrangements had to be discussed as Parliament reopened for business after the three-month summer recess. Mr Howarth has an office in the Palace, which he is likely to retain. And he said his secretary, Patricia Constant, would be true to her name.
Mr Howarth, whose defection was announced the Sunday before Tory conference in an elaborate media operation, already sounds like a partisan Labour MP. Last weekend he accused the Tories of peddling "smears and lies" against him.
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