Several hundred protesters this morning descended on the Aldermaston Atomic Weapons Institute for what Greenpeace, the organisers, called the world's biggest-ever nuclear weapons inspection.

With the Soviet Union gone, the veil of deterrence Trident was hiding behind vanished. (Photo: Greenpeace)

The demonstrators were objecting to building work at the top-secret site which they claim heralds a new generation of new nuclear weapons.

A Liberal Democrat MP, Norman Baker, and the founder of the Body Shop, Anita Roddick, joined around 400 demonstrators intending to pin legal advice that renewing the Trident nuclear weapons system would be against international law on to the security fence.

Superintendent Robin Rickard, of Thames Valley police, said that his officers were guarding the AWE to ensure that the protest passed off peacefully.

Ben Stewart, a spokesman for Greenpeace who attended the event, said: "The decision on Trident is exactly the same as Tony Blair's hypocrisy over the Iraq war and civil nuclear power.

"First he makes the decision in secret. Then he demands a public debate."

He added: "We are going to take photographs and pin legal advice to the fence suggesting that the government's Trident renewal would be illegal according to international law."

According to Greenpeace, Philippe Sands QC, of Cherie Booth's Matrix Chambers, has ruled that Mr Blair's policy could break the Nuclear Non-Proliferation Treaty, risking a breach of the same protocols he says that Iran must adhere to.

Renewal, replacement or upgrading of Trident is likely to breach Article VI of the Nuclear Non-Proliferation Treaty (NPT), Mr Sands claims.

Anita Roddick told the crowd at Aldermaston, in pouring rain: "Sixty years ago we invented a way to extinguish life on Earth at the touch of a button, which was one of the less impressive things human beings ever did.

"Now Tony Blair has the chance to leave an historic legacy to the world by making Britain the first UN security council member to say, 'We no longer want or need these monstrous weapons.'

"If he doesn't, he'll break international treaties and send an invitation to every nation on Earth to join the nuclear club."

At prime minister's question time last week, Mr Blair confirmed that a white paper on replacing Trident would be published before Christmas.

Although he has promised MPs a general vote on the issue - a substantial minority of Labour MPs is opposed - the Liberal Democrats are demanding a full debate and vote on a range of issues, including non-replacement and alternative weapons systems.

Guardian Unlimited © Guardian News and Media Limited 2006

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