The shadow foreign secretary has said that Britain does not have to choose between alliances with either America or Europe.

In a speech to the Conservative Foreign Affairs Forum on Wednesday, Michael Ancram set out Conservative backing for "the nations of Europe and America".

The speech comes amid scepticism in European capitals about US president George Bush's plans to tackle Iraqi attempts to acquire weapons of mass destruction.

The American administration's decision to impose tariffs on steel imports and its reluctance to intervene in the conflict between Israel and the Palestinians have also provoked a mixture of anger and concern among European governments.

But Ancram said that despite the disagreements, there are other options besides choosing to back America or Europe.

"It is a false choice because there is another. The nations of Europe and America, the one I strongly support," he said.

Ancram set out his view of Britain's role in ensuring Europe works closely with its American partner.

"A Europe which in terms of the relationship with America is not a rival but a complement, not a critic but a counsellor. We here in Britain can lead the way, bringing America and Europe closer together on the basis of the common interests which we epitomise."

Ancram also said the Conservative Party was committed to playing a leading role in an "effective and outward-looking Europe".

"We believe we are part of Europe, that our future lies within the European Union and that an effective and outward-looking Europe in which we can play our full part will be good for international relations generally and for our relations with the US in particular," he said.

"We believe that influence comes not from coercion or centralisation or harmonisation, or from hang-ups about single currencies or common foreign policies or European armies, but from cooperation and mutual understanding."

But while accepting Britain's role in the EU, Ancram also argued that the UK should seek to renegotiate Europe's treaties to return powers back to Britain.

"We should not be afraid to urge the re-opening of the treaties to bring Europe up to date with the modern world. We should seek constructively to reverse its centralising tendencies. We should challenge the aquis and urge repatriation of large parts of agricultural and foreign aid policy."

However, Liberal Democrat foreign affairs spokesman Menzies Campbell said: "This effort to appear constructive is pretty unconvincing from a party which since the last election has increasingly sounded like the provisional wing of the Heritage Foundation.

"The truth is that visceral anti-Europeanism still drives the Tories. If this was not the case then people like Kenneth Clark, Ian Taylor, and David Curry would be in the Conservative front line. The Maastricht rebels have taken over the Tory party and nothing can conceal it.

"This speech contains more contradiction than constructiveness," he said.