There may even be something unheard of at previous Anglo-French summits: a joint communique on a big issue. Joint communiques are the stuff of Franco-German summits; they are - or used to be - the instrument by which the Paris-Bonn axis imposed its will on the European Union. If the British and French were to frame one, and it is not entirely certain that they will, other EU governments would look around in some astonishment.
The issue is European defence policy. Tony Blair thinks there should be one. So did John Major's government, except that it insisted, like all previous British governments, that such a policy should have nothing to do with the European Community or Union.
Mr Blair caused some astonishment, and puzzlement, in European capitals - most of all Paris - last month when he announced that he was dropping the British veto on EU involvement in defence issues. He said it was time that Europe had its own capacity to act independently of the US in future European crises such as Kosovo. His mind was "open" on whether this should be organised at EU level. But there should be no European army as such and nothing should be done to undermine Nato.
The statement, made in a somewhat bungled interview with leading European newspapers, was written off at first as a desperate attempt by that nice young Mr Blair to remind other EU leaders that he was a European statesman too. It came just after Gerhard Schroder was elected as Chancellor of Germany and just before EU leaders were to meet in Austria for an informal summit, which would inevitably be dominated by the Euro (an issue from which Mr Blair is semi-excluded).
The launch was bungled because Downing Street warned The Times, the only British newspaper invited, that the Prime Minister was going to make an important statement on defence. The European correspondents were not warned. Mr Blair's comments were expressed, in any case, less forcefully than Downing Street had intended. The leading European papers downplayed his defence remarks; The Times put them on the front page.
The effect was to reinforce the first impression on the Continent that this was for domestic consumption: a "headline without a story", as one French government official put it. Pressed for detail, the Blair government had none; it was just trying to raise the issue, it said. "But hang on, you are the British," the other governments objected. "Your role in Europe is not to make visionary statements without substance. That is what we do."
In any event, the British suggestion made little progress at the Austrian summit, shot down by, of all people, President Chirac, a man who had previously pushed similar ideas himself. As a result, Downing Street began, in private briefings, to bad-mouth Mr Chirac, suggesting that he was not a serious or consistent politician (a suggestion which would cause little surprise in France).
Nonetheless, little by little, the French - both Mr Chirac and the Prime Minister, Mr Jospin - have come around to the view that something important has happened in London. There has been a flurry of meetings at official level to try to put some joint Anglo-French flesh on the bones of Mr Blair's idea. There is even talk of a pre-summit summit of the foreign and defence ministers of the two countries to consider possible wording for a Blair- Chirac-Jospin communique in St Malo on Friday.
The timing is good from the French point of view. There is a Franco-German summit earlier in the week. Seen from a Parisian perspective, it will do no harm for Mr Schroder, who has talked of a triangular Bonn-Paris- London relationship, to be reminded that triangles have three sides.
But how serious are the discussions on defence policy? What do they mean? The core issue is the lack of a joint European military capacity to put Europe's might where its mouth is. Common European foreign and security policy is fine, but lacks the ability, ultimately, to enforce its commitments. This was plain, once again, in the Kosovo crisis when the Europeans were unable to act without American help.
This is partly because of a lack of a political forum in which such issues can be discussed. The Western European Union (WEU) provides such a forum but has never worked effectively, partly because there has never been the will of member governments to allow it to work effectively.
The more serious issue, in the long run, is the Europeans' lack of the satellite, logistical and transport hardware to make such joint military missions possible. Nato strength in these areas is largely owned by the Americans. If the Europeans are to have an independent rapid-response and peacekeeping capacity, that implies substantial investment in spy and communications satellites, transport ships and planes. Who would organise such investment? Who would administer it?
Thinking until now has centred on the WEU, as a kind of diplomatic pontoon bridge between the EU and Nato. Mr Blair has said that this arrangement could remain and be strengthened. But he is, he says, also open to the possibility of creating a separate EU defence policy or bringing the WEU wholesale into the EU, for those countries who wish to participate. (This is a potential solution to the dilemma of the EU neutrals - Ireland, Austria, Sweden and Finland - who do not want to belong to a defence policy but do wish to belong to EU joint foreign policy.)
How far a joint Anglo-French statement may go towards tackling these issues is unclear. The core problems of logistical hardware have been part of the pre-summit talks. French officials say that they still suspect that the Blair government's original interest was to find an area of European policy in which they could move forward without flanking fire from the British Eurosceptic press. None the less, Paris realises that the British are now serious about tackling the formidable problems involved.Reuse content