LONDON, Dec 10: Fresh and apparently incriminating documents have come to light under the Freedom of Information Act on the way Britain helped Israel obtain its nuclear bomb 40 years ago, by selling it 20 tons of heavy water.

The Whitehall files not only confirm that Britain was a knowing party to the deal, but also contain subsequent intelligence assessments confirming that the sale of heavy water was crucial to Israel’s nuclear weapons programme.

It was first revealed earlier this year by BBC Newsnight that sale of heavy water to Israel had secretly taken place in 1958. But Kim Howells, a Foreign Office minister, subsequently claimed that ‘the UK was not in fact a party to the sale of heavy water to Israel’. He sought to blame Norway, saying Britain had merely negotiated ‘the sale back to Norway of surplus heavy water’.

But Mr Howells’s claims were undermined on Friday night when Newsnight produced documents from the National Archives. A Joint Intelligence Bureau report to spy chiefs on March 27, 1961, says: “The main Israeli achievement in the importing line relates to 20 tons of heavy water ... which the UK had contracted to buy from Norway and later found to be surplus to their requirements ... negotiations were undertaken whereby the water ultimately passed into Israeli hands.”

Contrary to Mr Howells’s claim that Britain could not impose safeguards, the papers also show that Britain deliberately agreed not to demand safeguards over the Israeli sale, and officials said it would be ‘over-zealous’ to do so.