Iraq Crisis: Angry Yeltsin warns Clinton he risks a third world war as fresh claims emerge of chemical and germ weapons

The Blairs flew into a very different US last night than the one they might have anticipated visiting a week ago. There is every chance that the matter of the threatened war with Iraq will nudge President Clinton's sex life from the top of the news agenda. Mary Dejevsky in Washington asks whether the old rapport will be renewed.

When Tony and Cherie Blair arrived in Washington for the first full- dress new Democrat-new Labour summit, the back-room organisers had much to be thankful for.

First, the summit was taking place as planned - and even a week ago, that could not have been predicted with any certainty. Secondly, Mr Blair would meet the President he had expected to meet, the President with whom he had so quickly established a personal and ideological rapport last year, the President who had deferred so graciously to his younger, newly elected host in London last June. Thirdly, the American media frenzy over the White House sex scandal had subsided enough for Americans to have at least half an eye out for something different. The visit would not be totally obscured, to put it delicately, by other matters.

Fourthly, the dispute with Iraq, which is portrayed in Washington as more serious than perhaps at any time since the end of the Gulf War seven years ago, provides a near-ideal topic for today's British-US talks. There is enough difference in emphasis to afford a discussion and sufficient agreement to fuel a "strongly worded" joint statement. Moreover, the distance between the British-US position and that of many other countries, European countries included, permits both sides to revive talk of the "special relationship".

The close political relationship between Downing Street and the White House since Mr Blair was elected, the frequent phone calls and the personal bonhomie between the first couples were hammered home by British and US officials in advance of the visit, with both sides stressing the unusual length (three full days) of the Blairs' stay and the session set aside for Clintonite "policy-wonking" - free discussion of political ideas - at the presidential retreat of Camp David, to which advisers and wives are invited.

This does not mean that the visit is free of risk, either for Mr Blair or Mr Clinton. Britain is not as convinced as America that existing UN Security Council resolutions are sufficient legal justification for a military strike against Iraq. As Mr Blair's dodging of a question on this subject during a pre-summit interview with US journalists showed, this is still a contentious question. So is the degree to which Iraq should be given hope of an end to sanctions.

When the Foreign Secretary, Robin Cook, visited Washington last month, he appeared to defer to the view of France and some other European countries in saying that Iraq needed hope that, if it complied with UN resolutions, sanctions would be lifted. Some US statements have taken a harsher stance. The distinction made by British officials between his visit, which was presented in the framework of Britain's presidency of the EU, and Mr Blair's visit, which is primarily bilateral in character, could pave the way for Mr Blair to articulate a harder British line on Iraq - at least for presentational purposes.

If Britain were seen to be too unconditionally in favour of US action, this could impair its continuing efforts at the UN to mobilise support for the US position.

Public unity on Iraq, however, along with broad agreement on such topics as Nato expansion, a continued international presence in Bosnia, and US backing for the Irish peace talks, is unlikely to divert the American media's attentionfrom the Clinton sex scandal. Small matter that the Blairs, the very model of "family values", are the ideal White House guests at this point.

The US media anticipates with some excitement the joint leaders' press conference. Scheduled for tomorrow morning, to catch peak evening television viewing in Britain, it will be the first time Mr Clinton has answered reporters' questions since his first, hesitant denials of the alleged Lewinsky affair.

It is unlikely that there will be no questions on this subject. The risk for Mr Blair is either that he is sidelined, as was Yasser Arafat, whose Washington press conference two weeks ago coincided with the start of the scandal, or that "family values" questions will also be directed to him, perhaps with reference to his Foreign Secretary, and that the substance of the summit will be obscured. At least, if Mr Blair finds himself facing sex questions, he has had ample time to prepare his riposte.