The EU's newest members are reviewing foreign policy. In Austria, Finland and Sweden - the three newest members and once self-proclaimed bastions of neutrality - the issue of whether to seek NATO membership is enlivening public debate.

There is a shared sense that the foreign policy imperatives which once underpinned the choice of neutrality in a continent split into ideological camps have become weaker.

"Neutral countries' foreign policy agendas do not clash with NATO enlargement any longer. It is becoming a purely domestic problem," said Ms Heather Grabbe, EU enlargement specialist at the Royal Institute of International Affairs.

In Stockholm this month, Mr Carl Bildt, leader of the opposition Moderate Party, suggested the time might be ripe for Sweden to consider NATO membership. For the Liberal Party, another NATO supporter, joining the alliance would allow substantial savings on the defence budget while maximising security.

The ruling Social Democrats say they have no intention of changing policy for the next five years, but observers wonder what will happen after that.

"It is pragmatism which led us to neutrality. Pragmatism should now rule as we consider NATO membership," a Swedish diplomat said.

The debate rages more furiously in Austria, where the coalition government was shaken by the decision of the junior partner, the People's Party, to call for NATO membership at a conference in July.

Austria is often seen as a natural candidate to accompany Romania and Slovenia in an eventual "second wave" of NATO expansion, following the first wave of 1999 that will admit the Czech Republic, Hungary and Poland.

Austria is the only country whose neutrality is enshrined in a treaty, but last month's NATO decision to incorporate three former Warsaw Pact states has increased the pressure to join the alliance. Neutrality, arguably a sensible arrangement for a small buffer state, becomes an unnecessary complication when enemies turn into good neighbours.

Even in cautious Finland, Mr Paavo Lipponen, the Prime Minister, recently had to restate the once-obvious case for neutrality. While the government is not yet seeking NATO membership, many Finnish specialists argue that the alliance's special relationship agreement with Russia, signed in May, may mean that key European security questions will be settled without Finnish involvement.

The answer, they say, is to join NATO.

In practice, joining NATO would not represent a radical departure from the present situation. The three neutrals have observer status at the Western European Union, the EU's putative defence arm, and are members of NATO's Partnership for Peace programme. Sweden sent troops to Bosnia, as did Austria, which was also part of the Italian-led force in Albania.

The neutrals' experience of UN style crisis management and their endorsement of the 1992 WEU peacekeeping guidelines make them potential participants in most future NATO operations.

Nonetheless, many obstacles remain. Article 5 of NATO's Atlantic Treaty - covering mutual military guarantees - remains taboo for large segments of the Austrian, Finnish and Swedish populations. Nor is the idea of associating with an organisation with nuclear weapons popular.

Yet the political atmosphere has relaxed tangibly.

Observers do not foresee a shift of policy in Sweden under the present government, and agree that Finland would probably not move alone.

In the coming months, the spotlight will focus on Austria as NATO proceeds with its planned enlargement.