EU leaders, due to meet next week in Helsinki, will agree to develop by 2003 a multinational rapid reaction force of 50-60,000 troops to deal with crises where the US does not want to become involved.
The decision will give practical effect to agreements in principle at the Amsterdam and Cologne summits to develop a "European security and defence identity" for peacekeeping and related purposes.
Diplomatic sources say that agreement at official level has been reached to begin the process of asking member-states to list what specialist and general elements of such a force they would be willing to prepare to deploy if called upon. Member-states unwilling to participate in individual missions will not be required to do so.
The Helsinki summit, on Friday and Saturday, will also establish military/political structures within the European Council to co-ordinate new EU operations, while stressing the primary role of NATO in the collective defence of its members.
The leaders will agree that member-states should be able to deploy a force of up to 15 battalions at 60 days' notice - a force
capable of sustaining itself logistically for a full year. Such a capability would also involve smaller units with an even faster reaction time.
On structural reform, the summit is likely to leave the door open to the ambitious treaty reforms advocated by the Commission President, Mr Romano Prodi, in spite of strong reservations among member-states.
Diplomatic and Commission sources suggest the Finnish EU presidency will report to heads of governments that there is no appetite yet in capitals for the radical reforms advocated by Mr Prodi. It will however draw up a remit to launch a new treaty-changing Intergovernmental Conference, to allow it to go beyond the limited institutional "leftovers" of Amsterdam which it must address.
Mr Prodi was anxious to avoid an early rush to judgment at the summit on his radical proposals and has persuaded the Finns to allow the European University Institute to submit a draft amended treaty to the IGC in the spring, on which it just happens to have been working. Mr Prodi hopes to make future treaty amendment easier by splitting it into two parts, a constitutional core still requiring unanimity and an IGC, and a policy text which could be changed by a meeting of heads of government acting, for the most part, by majority.
He also wants to make the Amsterdam Treaty's provisions for "flexibility" - the possibility for embarking on projects with less than the full membership - easier to operate.
The presidency text on the IGC will make room for the possibility that institutional changes arising from the defence debate and next year's drafting of a charter of fundamental rights may also require treaty provision.
Lawyers are still arguing about whether granting authority to a new military/political committee to run peacekeeping operations will require a treaty amendment. Dublin will certainly be among those who hope not.
Other once-difficult elements of the Helsinki summit agenda are also falling into place. There is agreement that Bulgaria and Romania will be included in accession negotiations, as well as Latvia, Lithuania, Slovakia and Malta.
It also appears certain that Turkey will be given "candidate" member status, although some states are still hoping to see Ankara come up with a gesture of its good faith - the most likely is an expression of willingness to be bound in its territorial disputes with Greece in the Aegean by a ruling of the International Court in The Hague.
Substantial harmony at the summit is likely to be marred, however, by Britain's continuing refusal to countenance a minimum tax on non-resident savings accounts. Few expect progress at Helsinki and sparks could fly.