Labour MPs have attempted to pile the pressure on embattled Chief Whip Andrew Mitchell amid renewed demands for him to be sacked over his row with Downing Street police.
Shadow leader of the House of Commons Angela Eagle claimed Mr Mitchell kept "changing his story" and challenged him to divulge to MPs "what he actually did say".
Andrew Lansley defended Mr Mitchell in the Commons from a flurry of remarks from the Opposition benches relating to Mr Mitchell's confrontation with officers, saying he was "doing his job well".
On Wednesday Labour leader Ed Miliband used the first Prime Minister's Questions since the incident last month to denounce Mr Mitchell, saying he should have been arrested like any other "yob" who had sworn at officers. And at Wednesday night's weekly meeting of the Conservative backbench 1922 Committee at Westminster, four Tory MPs were said to have voiced concerns about Mr Mitchell's position.
Speaking on Thursday at the start of Commons Business questions, when Mr Mitchell was absent from the chamber, Ms Eagle said: "As the Leader of the House has already announced, next week there'll be an Opposition day debate on the police.
"There's a long standing convention that the chief whip in this House is seen, but not heard. The current Government Chief Whip who is inexplicably not in his place today, would be well advised to observe that convention outside this House too."
She said police reported Mr Mitchell as saying officers were 'plebs, who should know their place'.
She added: "The Chief Whip keeps changing his story and I would have wanted to say to him, had he had the courtesy of this House to attend today, that he should come to the despatch box and tell the House what he actually did say. But perhaps he's too busy repairing relations with the Conservative backbenchers to bother to attend Business questions."
Leader of the House of Commons Mr Lansley replied: "The Chief Whip is doing his job well ... the Chief Whip knows and made clear that he had made a mistake, he apologised for that, the police officer concerned accepted it and the Metropolitan Police accepted it. I will take no lectures today or indeed next Wednesday when the Opposition day debate on the police takes place about the support this Government gives to the police."
To laughs from the Opposition benches, Clive Efford, Labour MP for Eltham, asked: "Can we have a debate on the place of plebs in society?"