Jack Cunningham: "We need to put this matter behind us"

Mr Cunningham - who as the cabinet enforcer is responsible for discipline - said ministers had to stop following their own agendas and stick to the government's.

The downfall of former trade secretary Peter Mandelson has led to more speculation about Cabinet in-fighting.

Mr Mandelson quit on 23 December over an undeclared £373,000 loan from former paymaster general Geoffrey Robinson, who also resigned.

Although the source of the leak about the secret loan has yet to be discovered, speculation centres on Mr Mandelson's enemies at the Treasury.

Jack Cunningham: Wants end to

Downing Street has no direct evidence Chancellor Gordon Brown's press secretary Charlie Whelan is behind the leak, but it would not be the first time the team at No 11 Downing Street have settled old scores.

Mr Cunningham told BBC Radio 4's Today programme: "We need to put this matter behind us and put behind us some of the activities of people who may think they can have their own agenda on their own account whether it conflicts with the government's agenda or not.

"I say that cannot be allowed to happen, cannot be allowed to continue and we must put an end to it."

Mr Cunningham said he also wanted an end to secret briefing of journalists.

Clive Soley: "People want to judge us as doing things properly"

Chairman of the Parliamentary Labour Party Clive Soley also suggested "disciplinary action" should be used to stem feuds within the party.

Mr Soley told BBC Radio 4's Westminster Hour: "I've had my own worries off and on as to whether there were people ... settling old scores.

"In my view, if there is evidence of that, those people need to go and we need to be very tough on that.

"If people are going round trying to settle old scores that is unacceptable."

Tories keep up pressure

Deputy Conservative leader Peter Lilley has written to Cabinet Secretary Richard Wilson asking him to investigate how many ministers had been offered loans by Mr Robinson and to look into the connection between the former paymaster general and Mr Brown.

Peter Lilley: We need a full inquiry

He told the BBC: "It is not possible for the prime minister to brush this aside as if his cronies do not have any rules applied to them that apply to everyone else."

Shadow Foreign Secretary Michael Howard dubbed Mr Robinson "the Godfather of New Labour".

Charlie Whelan: Gordon Brown's spin doctor

Meanwhile, Warnaco clothing millionairess Linda Wachner has come to the defence of Mr Mandelson, telling the Times newspaper that he had done nothing wrong in accepting three free flights in her personal jet.

She said: "He has done absolutely nothing to help my company, he was my personal guest. I have a lot of friends who are in government."

Mr Mandelson admitted accepting the flights but refuted claims that he should have declared them.