The new Foreign Secretary travelled to Paris and Bonn in unaccustomed style, but he quickly found the right notes to strike with his opposite numbers
It was Douglas Henderson, the new Minister of State for Europe, who summed it up. As the RAF BaE 146 touched down at Paris's Villacoublay military airport after an in-flight breakfast of bacon, omelette, hot rolls and - of course - Fortnum and Mason marmalade, the one-time engineering apprentice and trade union official from Fife surveyed the scene, starched napkins, silver cutlery and all, and declared: "Well, it beats flying Britannia to Tenerife."

You still feel that Henderson - a smart man who, in the 72 hours since he was appointed to join his boss Robin Cook at the Foreign Office on Sunday, has learnt more about the EU than most of us learn in a lifetime - thinks he will suddenly wake up and find it's all a dream. He knows this is a serious job - coveted before the election by Peter Mandelson, no less. But now, standing in the sumptuous tapestried solemnity of the Quai D'Orsay (at the steps of which the French lay on not just a red carpet, but a 14-strong sabre-brandishing guard of honour, splendid in gold braid and kepis, formed by the elite Garde Republicaine), he just can't stop himself breaking out in a grin or a wink.

It's partly, of course, that the trappings of power pass so swiftly and conspicuously from vanquished to victors in the British system. It's not just the hushed, respectful tones of the RAF personnel who carry the bags at Northolt, or the blue, armoured embassy Rolls Royce in which the new Foreign Secretary sweeps through Bonn (Henderson having to make do with a mere Jaguar) or the company of some of the keenest brains in Whitehall, like Paul Lever, the FCO's deputy secretary for Europe, and Jeremy Greenstock, the political director. It's also that everyone wants to hear what you say and know what you think.

Nigel Scheinwald, the Foreign Office's head of news, strains to hear what Cook is saying to a handful of journalists above the roar of the 146's jet engines: after all, this will be the New Line, distributed to dozens of news-hungry British embassies, to the world's press, to foreign governments. After less than a week the Line is still emerging. That's the peculiar thrill of a new government. Every remark the Secretary of State makes, every nuance, almost every raised eyebrow, helps the eager officials first to grasp what the Line will be, and then, with clinical efficiency, to ensure that it prevails. They are too professional to say so, but it's a Line they actually want to hear. Being nice to foreigners from time to time makes quite a change.

And this was very much - as the Foreign Secretary himself could not resist calling it - Cook's tour. Unlike Henderson, Cook has had almost three years to prepare for this moment. (Though even he momentarily forgot how much has changed: during a meeting with Herve Le Charette, the French Foreign Minister, who chain-smoked his way through a working lunch with his new counterpart, of lobster, lamb, red fruits and ice cream, Cook referred to what "Labour", rather than The Government, would do).

Like Gordon Brown, with his decision on autonomy for the Bank of England, Cook hit the ground running, saying that Britain would sign up to the Social Chapter at next month's Intergovernmental conference in Amsterdam. The move reverberated instantly through Europe. And it set a wholly new tone, first for Cook's trip this week, and second for the talks about the IGC which Tony Blair will have in London today with Wim Kok, the Dutch premier and holder of the EU Presidency.

There was also a modest stroke of good luck: Klaus Kinkel was not back from Egypt until Wednesday afternoon so Cook could go to Paris in the morning - making quite a lot of the fact when he got there that it was the first foreign country he had visited since the election - without offending Kinkel by going to Bonn second.

Just to make sure, when the talks began over asparagus, beef and wine with the German Foreign Minister at the coincidentally named Kinkel-Stuben restaurant, the Foreign Secretary promised to find a Cook's Restaurant for Kinkel to visit in London. This was not, perhaps, the greatest joke in the history of British diplomacy. But it seemed to break the ice. One German official sought out a senior British diplomat to say how impressed he had been not only by Cook's mastery of his brief but by his sense of humour. The talks produced one startling discovery. Kinkel appeared distinctly uncertain about the intricacies of the quota-hopping row over fishing. Was it possible that Tory ministers had not been quite as angry about the issue in private as they were in public? Cook made nothing of this, of course. Instead, in a TV interview he neatly turned the Tories' "puppet Blair" campaign poster to the advantage of future Anglo-German relations. "It was," he said magisterially, "quite inappropriate to the head of another government."

Another good omen was the extraordinary impact the Labour victory has had on French, and to an extent, German politics. In France there was extensive coverage of last Thursday's election with the newspaper Liberation carrying 24 pages, edited in London. The event has become an issue in the French elections, with the right claiming that Blair won because he moved his party away from the left, and the socialists claiming that it showed that the left can win. "Every politician in France wants to be Tony Blair," a French TV journalist told Cook in Paris. "Everyone wants to be Tony Blair," Cook replied.

Lionel Jospin, the French socialist leader, in his private talks with Cook in cramped offices in the rue De Vaugirard (offices which are more Transport House than Millbank), wanted to know all about New Labour and was gripped by the conquest of the centre ground - though unlike Blair he has the disadvantage of competition from the communists on the left.

For Oskar Lafontaine, chairman of the German SDP, who greeted Cook with an enormous bear hug, the Blair victory has not been an unmixed blessing. The British party were shown a newspaper headline quoting Gerhard Schroder, Lafontaine's popular, formidable and modernising rival, saying that he was the Tony Blair of the German left. If Cook, as a possible left-wing challenger to Blair after John Smith's death, felt a sneaking twinge of sympathy, he certainly wasn't letting on.

A clear New Labour strategy towards Europe is starting to emerge. Aside from his opposition to the single currency, Cook is a Euro-pragmatist rather than a Euro-sceptic. Any disappointment in Paris and Bonn about Britain's reluctance to join the single currency in the first wave was offset by Cook's clear promise not to obstruct its formation during our Presidency in the first half of 1998. It's true that the increasingly Europhobic tone adopted by both the main parties in the run-up to the election reflected, and perhaps contributed to, a mood of public suspicion about Europe. That mood was fuelled by The Sun, Labour's powerful new ally from the nationalistic right.

That mood, Cook appears to believe, could change quickly if Britain is seen to secure even quite modest successes in Europe without giving ground on issues like borders or foreign policy. Even The Sun, which has had to perform a somersault roughly equivalent to that of the communist Daily Worker in the wake of the Nazi-Soviet pact, was curiously muted last Monday about the decision to go ahead and sign the Social Chapter. Is it so unimaginable that we could see headlines in it like "Blair pulls off deal for Britain"?

Cook's strength is that he has a persuasive story to tell about the forthcoming IGC which belies the Tories' pre-election rhetoric about the surrenders being prepared by Labour. He was, by all accounts, impressively robust in his talks with Kinkel and Le Charette about Britain's insistence on maintaining border controls, on keeping the EU out of defence, and on the dangers that so-called "flexibility" proposals could lead to an inner cabal, its nucleus formed by the countries which join EMU. On this last - and potentially still one of the most difficult subjects for Amsterdam - Cook was clear: such flexibility shouldn't apply to the main economic areas of the EU or to foreign policy. And it should only apply in areas like immigration and justice if all 15 states agreed and probably more than half - perhaps 10 - agreed to take part. And he argues that Britain is much likelier to get its way on all this if it doesn't make a virtue out of challenging every single other proposal. Cook is careful not to promise a successful outcome: "By not fighting needless battles," he says, "we will be able to focus energies on the battles we must win."

But he is also careful to stress that in several, if not all, of the areas in which Britain is prepared to reach agreement, she has a specific interest in doing so. The Social Chapter is being signed, he says, not to be nice to Europe, but because British workers should have the rights embodied in it. On the European Parliament he even seemed to be baffled why the Tory sceptics oppose the new powers he and Blair are ready to concede. So far from being an integrationist move, he says, it will help Strasbourg to impose a "democratic check" on the EU's other institutions. It's "totally weird" of the Tories to oppose ending the veto on anti-fraud measures when it simply means that a fraudulent country can avoid penalties. And so on.

It's almost impossible to underestimate the impact of this change in language. Particularly since there are growing signs - evident in Cook's talks with Kinkel this week - that the Germans are now anxious to get through the IGC with the minimum of fuss in order to clear the decks for EMU. To be sure of this change of public mood, the government needs to make headway on lifting the beef ban - which it has always held up as the most catastrophic failure of government policy.

Cook shows every sign of knowing this; but he is guarded. It will, he says, need time. A sure sign of the new alignment is that the Italians have started complaining vociferously to London about all this talk of France, Germany and Britain as the "big three" of Europe. It seems increasingly likely that the public mood could start changing faster than looked possible before the election, as a result of a successful, and relatively non-integrationist, IGC. Britain remains hostile to grand integrationist designs. And so do Cook and Blair. But real leadership in Europe would be a novel and attractive prospect. It could even make some Tories wonder if they have really been fighting the wrong battles.