NATO Reconsiders Its Nuclear Arsenal : Military: Britain discloses a U.S. request to deploy aircraft capable of carrying atomic weapons at its bases.

Defense ministers of the North Atlantic Treaty Organization took the first step Wednesday toward potentially major changes in NATO’s arsenal of short-range nuclear weapons.

Ending a two-day conference, NATO’s Nuclear Planning Group directed an international body of government experts to study how reductions in the conventional forces of NATO and the Warsaw Pact could change the number and composition of the West’s battlefield nuclear weapons.

At the same time, British Defense Secretary Tom King disclosed that Washington has asked Britain to consider an unprecedented deployment of nuclear-capable B-52 heavy bombers or of F-15E nuclear strike aircraft at British air bases.

King said that London has made no decision on Washington’s request or on the number of aircraft that might be based in Britain. But in a strong hint that the move is imminent, he added that London and Washington alone can make the decision without formal consultation among NATO allies.

The introduction of either plane to Britain, a move designed to offset the loss of medium-range missiles withdrawn under the Intermediate-range Nuclear Forces Treaty, could reactivate Western Europe’s politically dormant peace movement. It also would probably draw harsh Soviet protests at a delicate time in negotiations over reductions in aircraft.

Meeting against the political backdrop of sweeping changes in the Soviet Union and Eastern Europe, the 14 participating NATO defense ministers ended their talks at this seaside Portuguese resort with an agreement to defer active debate on a range of other divisive nuclear modernization issues.

In launching the study of short-range nuclear needs, NATO Secretary General Manfred Woerner said that the final report will reflect the consensus among the Western allies that “we will still need a number of modern and credible nuclear weapons to underpin our NATO security structure.”

Beyond that, however, NATO members are at odds over whether and how to modernize NATO’s arsenal of short-range nuclear weapons, as well as which NATO members should carry the burden of deploying new nuclear weapons on their soil. But the allies set aside those simmering disputes while they await the outcome of the changes in the Soviet Union and Eastern Europe.

The NATO meeting came as the Soviets launched proposals that could profoundly affect the Atlantic Alliance. On Monday, Soviet Foreign Minister Eduard A. Shevardnadze called for NATO and the Warsaw Pact to negotiate the dissolution of both alliances by the year 2000. Woerner dismissed Moscow’s call as “a longstanding aim” of Soviet policy.

The current upheaval in the Eastern Bloc has made “this (a) dangerous time,” added British Defense Secretary King. “It is quite important in this time of manifest change in the Soviet Union that NATO stability . . . remains invariable.”

Several of the allies differ on whether, when and which short-range nuclear weapons should be subject to negotiated reductions, and whether modernization should proceed.

Hoping that the future of Soviet defense policy will be clearer by then, NATO members said they will not debate the terms of that negotiation now. France and Britain, which maintain nuclear forces independent of NATO’s, are wary of participating in any negotiations that might seek to limit their nuclear weapons. France does not attend meetings of the Nuclear Planning Group, and British officials said it is too early to discuss the short-range nuclear talks.