He is accompanied, as for the General Affairs Committee he chaired in Brussels last month, by Gaynor Regan, for whose trip he is personally paying. In Brussels she will keep discreetly out of sight until the flight home. One topic dominates conversation: Iraq, and the first reports filtering out of Baghdad is that Kofi Annan is close to a deal. Mr Cook "strongly resists" suggestions he has been less hawkish than Tony Blair. He will later tell Alastair Campbell he was sorry to see "crap" to this effect in the newspapers and that it certainly didn't come from him.
But he is proud of Britain's role persuading the US, after Washington's reluctance, to back Mr Annan's mission to Baghdad. It was at a crucial meeting in London on St Valentine's Day at which the plot to send Mr Annan to Baghdad with a clear mandate was agreed, between the FCO's Middle East Regional Director, Derek Plumbly, and his US and French counterparts.
1915 Sunday: Mr Cook arrives at the official residence of Sir Steven Wall, British representative to the EU. At the time of the last Gulf war, he was even closer to the centre, working for John Major in the private office at 10 Downing Street. But now the crisis has come to him, in the form of the Foreign Secretary. In a cloakroom off the hall, Mr Cook takes a call from Madeleine Albright, US Secretary of State. She has spoken by telephone to Mr Annan, who believes he has a deal which can be made to work. In a few minutes he is briefing the Prime Minister, who has spoken to President Bill Clinton, on the Albright call. The British are now clear Mr Annan has a deal he thinks can work. But Mr Annan has been hesitant to give the details over the telephone. Neither the British nor the Americans are clear whether President Saddam Hussein is for real on the issue of Unscom's free access to the compounds of the so-called presidential palaces, which are believed to house facilities for making, storing or documenting biological or chemical weapons. Mr Blair and Mr Cook agree to be cautious and stick to the line that they will need to see the fine print.
By this time Sir Steven is edgy. Three EU commissioners are waiting to have pre-dinner drinks with Mr Cook and they are running out of small talk. But Sir Steven also knows he cannot do other than wait. After dinner Mr Cook starts a briefing meeting with officials, including Sir Steven, the FCO's political director, Jeremy Greenstock, and Emyr Jones Parry, senior Europe man in London, on the next day's council. He runs through the business - China, the EU, Cyprus and Iran. But Iraq can't stop intruding. First, it is a topic for the Council meeting. Despite their agreement to the British-sponsored UN resolution in New York, the French Foreign Minister, Hubert Vedrine, is likely to be difficult. Mr Cook muses that, given what is happening in Baghdad, "perhaps Iraq will go through sweetly. But I can't believe we'll get away without a tour de table." He's right. Tomorrow it will take him two hours to get an agreed text insisting unequivocally that President Saddam must conform to the latest deal.
Then it's time for another call from Mr Blair - and this time he has spoken to Mr Annan, who is still reluctant to spell out details on a telephone line from Baghdad. But he is firm he has a deal which stays above the bottom lines the Security Council armed him with when he went to Baghdad. It is President Saddam who has done all the conceding. Tired but cheerful, Cook asks Sir Steven for an orange juice to take to bed.
0830 Monday: This is the moment everyone has been waiting for. Jurgen Trump, Secretary-General of the European Council, has his office in the Justus Lipsius EU building taken over by Mr Cook and his team to watch the Annan press conference on CNN. When it is delayed, Mr Cook thinks about whether he should go on the Today, but not for long. As he points out, even if the press conference hasn't happened by then (which by the time he does speak to Sue MacGregor, it has), "I would be very nervous about leaving a vacuum for others to fill."
When Mr Annan begins to speak, he is lavish in his thanks to President Saddam and Tariq Aziz for his reception in Baghdad. The officials are impassive but there is an unspoken question. What if Mr Annan has shifted ground - making fools, especially of the British, who had urged the US to back his mission? But then he says diplomacy is most effective when backed by "firmness and force". Mr Cook relaxes.
He says later: "If there had been no pressure on Saddam, there would have been no deal from Saddam." He still insists the Government cannot be certain until today's meeting in New York, when the Security Council will discuss the text. But he is hopeful. "A diplomatic solution was always my preferred option," he says.
The day seems over - but Mr Cook still has an EU General Affairs council to chair. And a lunch of all 15 foreign ministers. And a press conference at the end of it. And three meetings with the Baltic states. Then another press conference. Somehow he has to fit in - at lunchtime - one more call to Mrs Albright. She was in bed in Washington when Mr Annan was speaking in Baghdad and Cook gives her all his impressions. The line is agreed. It's been a long day, but Mr Cook flies home at 10pm a lot more optimistic than when he arrived.Reuse content