Gwyneth Dunwoody has attacked a "concerted effort" by government whips to scupper Robin Cook's plans to modernise the selection of Commons committee members.

In the Commons, Dunwoody, whose sacking as transport chairman led to a rethink of the appointment process, said the defeat was a backward step.

"The leader of the House has worked very hard to improve and increase the powers of the House of Commons and to modernise," Dunwoody told MPs during Thursday's Commons business statement.

On Tuesday, MPs unexpectedly voted against the select committee overhaul and Labour whips were accused of pointing to the No Lobby saying "PLP this way" in a bid to dupe backbenchers into voting against the plans.

"Is it not of considerable regret that on Tuesday there was a concerted effort by the government whips office to encourage MPs in to the opposite lobby?," she asked Cook.

Dunwoody questioned the status of the free vote - in which Cook's proposals to establish a committee of nomination was defeated by 209 votes to 195.

"Will he not address the question of the very interesting definition of a free vote as we seem to have lost an interpretation that could be clearly understood?," she demanded.

Cook warned his Labour colleagues that he would remember their rejection of his reforms when there was next a row over select committee membership.

"I regret the motion I put before the house did not command the majority," he said.

"The house has spoken and I have taken careful note of what was said by those who voted the other way.

"And the next time they are unhappy with membership of a select committee I shall remind them of Tuesday."

Asked by Sir George Young whether the Commons leader was intending to "revisit" the proposals, Cook revealed that his motion had taken several weeks to compose, only emerging after "painful negotiation and compromise".

"The house was given the opportunity to vote for a different system, it voted to stick with the present system. It will be some time before I feel able to revisit it."

The setback led to angry exchanges at Wednesday's meeting of the parliamentary Labour Party.

On Tuesday Cook urged MPs to vote for the new system saying it was the "biggest package to strengthen select committees" for two decades.

"The package will greatly strengthen the select committees. It will give them more resources, more focus and more transparency," he said.

"The committee will reinforce the standing of select committees and make it clear that nomination is independent of the control of party or executive machine.

"As a result, the select committees of the House will carry greater legitimacy, command greater confidence and bring greater authority to their task of scrutiny."

Lib Dem MP Paul Tyler called on Cook to demand the resignation of the government chief whip, Hilary Armstrong.