The attack followed an admission by Malcolm Rifkind, the Foreign Secretary, that there would be no hard negotiations in the inter- governmental talks on the future of the Union until after the next election. "I don't expect the negotiating to become really serious until after our election on the issues where there is a difference between ourselves and the Labour Party," Mr Rifkind told BBC Radio 4's Today programme.
"Because, obviously, what other European governments are waiting to see is if there was a change of government in this country, then some of the demands from Brussels would simply fall into their lap. They would not need to negotiate.
"So . . . they will wait to see the outcome of the general election."
But with Conservative ministers directing all their attention to the campaign for an election that could still be up to four months off, Mr Cook condemned the paralysis at the heart of government.
"It is not only Britain that is now being held back by this lame-duck government," he told The Independent, "but on the Foreign Secretary's admission, the whole of Europe. I am glad Mr Rifkind has admitted that the rest of Europe expects Labour to be elected."
The Foreign Secretary's statement also raises the question as to whether any agreement can possibly be reached on the future of the Europe package in time for an Amsterdam summit in June.
If no substantive negotiations are to be held until after the election, and the election is delayed until 1 May, there would be insufficient time for any government - Tory or Labour - to finalise agreement on a number of issues, such as qualified majority voting, that must remain controversial for both parties.
The Conservative strategy is to portray Tony Blair as the Brussels "poodle" who will roll over and concede critical elements of British sovereignty in the talks.
Labour replies that Mr Blair can be as sceptical as John Major on essential questions, but he does not have to look over his shoulder at a recalcitrant and rebellious party which gives him no room for manoeuvre in European talks.
The extent to which the election campaign will dominate the Westminster and Whitehall agendas for the new year was illustrated by two further developments yesterday.
First, the Conservative Research Department issued a briefing paper alleging that Labour was about to embark on a "negative campaigning" spree in January; denigrating its opponents rather than selling its own positive message. The Tories alleged that Labour was planning to spell out the "nightmare vision" of the country if Mr Major won a fifth term of office for the Conservatives.
While Labour claims that the Tories are planning a pounds 7m poster campaign, the Tories said all the evidence showed that Labour was being relentlessly negative, with its "Enough is enough" campaign.
Secondly, Labour, equally conscious of the Conservative capacity for negative campaigning, is reminding all frontbenchers that they must make no statements that might be taken to commit Labour to spend more money in government.
Ministers last month totted up the costs of every Labour spending commitment they could possibly pin on their opponents, and came up with a figure of pounds 30bn.
That figure will be used to sustain a repeat of the highly successful 1992 Conservative election campaign theme; that Labour will have to finance its alleged spending commitments with a secret "tax bombshell" for middle- income families.