Robin Cook last night made a surprise intervention in the Whitehall row over the decision by Dame Stella Rimington to publish her memoirs by calling on the former head of MI5 to think again.

His intervention, which came after a rare Commons debate on the security and intelligence services, contrasts with the implicit backing she received from Downing Street when her decision was leaked last month.

It is all the more surprising since the foreign secretary is responsible for MI6 and GCHQ but not for MI5 which is answerable to the home secretary, Jack Straw.

Whitehall officials believe the original leak - to the Sun newspaper - came from MI6 seizing the opportunity to embarrass its "sister service".

Mr Cook told MPs he understood Dame Stella had not yet submitted her draft to a publisher. "There is still time for her to reflect on whether it would be right for her to do so," he said.

Mr Cook said Dame Stella's text had been submitted for scrutiny by the security agencies and she had given her agreement that nothing would be published that would "undermine national security"

He added: "While there may be nothing that would be of direct compromise to national security, I detect that MPs ... would wish her to reflect on the example it would set and whether it would be wise to proceed in this way."

Tory MPs had earlier criticised her decision to write her memoirs.

The government, meanwhile, was pressed to set up a special tribunal to allow officers of the three security and intelligence agencies to air their grievances.

A number of Labour backbenchers also urged the government to establish a Commons select committee to monitor the agencies's work .

Pressure for a special tribunal came from Tom King, the former Conservative cabinet minister and chairman of the parliamentary intelligence and security committee which meets in private, whose members are appointed by the prime minister, and whose mandate is limited.

Dale Campbell-Savours, a Labour member of the committee, added his voice to the idea. He said security service employees needed a system through which to pursue grievances. He added that potential whistle-blowers should be allowed to go to their MP.

Richard Tomlinson, the renegade MI6 officer jailed for breaking the Official Secrets Act and now on the run in Italy, was prevented from taking his case to an industrial tribunal after he was sacked.

At the government's behest, he has been expelled from France, Switzerland, and Germany, after threatening to write a book. David Shayler, the former MI5 officer now living in Paris, has criticised the existing system whereby staff with grievances can go to a government-appointed staff counsellor.

Alan Beith, Liberal Democrat deputy leader who is also a member of the King committee, told MPs the greatest difficulty the body had was in obtaining information on advice given to ministers.

In a reference to the Melita Norwood spy saga - whose handling was attacked in a report by the committee last week - he said the central issue was "who knew what and when".

He added: "There really is no argument now that mistakes were made by the security service and by the home office, both over the failure to consult properly about non prosecution and about the handling and publication of the material."

Earlier, Mr Straw said MI5 had learned "a great deal" from the affair. The ISC report said ministers were kept in the dark about Mrs Norwood's role as a spy which was minor but was exaggerated afterthe publication of a book by the former KGB officer, Vasili Mitrokhin, last year.

Ann Widdecombe, the shadow home secretary said she found it "regrettable that confessed traitors such as Melita Norwood would never be prosecuted for betraying their country".