By Meirion Jones
The UK supplied Israel with quantities of plutonium while Harold Wilson was prime minister, BBC Newsnight can reveal.
The sale was made despite a warning from British intelligence that it might "make a material contribution to an Israeli weapons programme".
Under Wilson, Britain also sold Israel tons of chemicals used to make boosted atom bombs 20 times more powerful than Hiroshima or even Hydrogen Bombs.
In Harold Macmillan's time the UK supplied uranium 235 and the heavy water which allowed Israel to start up its nuclear weapons production plant at Dimona - heavy water which British intelligence estimated would allow Israel to make "six nuclear weapons a year".
Last August on BBC Newsnight we revealed the first British/Israeli deal, the sale of the heavy water, but the government responded by telling the International Atomic Energy Agency the UK was not a party to any sale to Israel and that all it did was sell some heavy water back to Norway.
Hundreds of shipments
Using Freedom of Information, Newsnight has obtained top secret papers. They show Foreign Minister Kim Howells misled the IAEA and that Britain made not one, but hundreds of secret shipments of nuclear materials to Israel.
Tony Benn, who was Minister of Technology in 1966, is shocked to learn of the sales
Tony Benn became Minister of Technology in 1966 while the plutonium deal was going through. The nuclear industry was part of his "white heat of technology" brief but no one told him that we were exporting atomic energy materials to Israel.
"I'm not only surprised, I'm shocked," he says, adding that neither he nor his predecessor Frank Cousins, who was a member of CND, agreed to the sales.
Benn says he always suspected civil servants were doing deals behind his back but he never thought they would sell plutonium to Israel. "It never occurred to me they would authorise something so totally against the policy of the government."
Back in August 1960 covertly taken photos of a mysterious site at Dimona in Israel arrived at Defence Intelligence Staff (DIS) in Whitehall. A brilliant analyst called Peter Kelly immediately realized they showed a secret nuclear reactor and he alerted the rest of British intelligence.
Kelly recognized it was a French reactor and soon discovered where the heavy water to run it had come from.
Selling plutonium to Israel was against UK government policy
Britain had bought heavy water from Norsk Hydro in Norway for its nuclear weapons programme but found it was surplus to requirements and needed a buyer. The papers obtained by Newsnight show that a company called Noratom acted as a consultant and arranged the deals in return for a 2% commission.
Britain knew all along that Israel wanted the heavy water "to produce plutonium" and Israel paid the full military price - £1 million - to avoid safeguards to stop the plutonium being used to make nuclear weapons.
Kelly discovered a charade was played out with the UK and Israeli delegations sitting in adjacent rooms while Noratom ferried separate contracts to and fro so Britain could say they hadn't signed a deal with Israel.
Once the press heard about Dimona in December 1960 there was an international outcry. Israel put out a cover story that it was a small research reactor. This did not fool Kelly. Using the figure of 20 tons of heavy water he estimated that Israel could build a reactor capable of producing "significant quantities of plutonium".
Michael Crick has used Freedom of Information to obtain secret papers
British intelligence learnt there was also a reprocessing plant and concluded "the separation of plutonium can only mean that Israel intends to produce nuclear weapons". Kelly even discovered that an Israeli observer had been allowed to watch one of the first French nuclear tests in Algeria.
Kelly and his colleagues in intelligence soon found their views about Israel were being challenged by Britain's representative at the IAEA Mike Michaels, who worked for one of the main figures in Harold Macmillan's Cabinet - Lord Hailsham.
Michaels received a JIC report early in 1961 estimating Israel would take at least three years to make enough plutonium and then another six months to work out how to make a bomb.
But it occurred to him that a friendly power might give Israel a small sample of plutonium to speed up the process. "Perhaps the French have supplied a small quantity for experimental purposes as we did to the French in like circumstances some years ago," he noted in the margin of the report. A few years later Michaels persuaded the UK to sell Israel a small sample of plutonium when he was aware - as this note shows - that this might cut months off the time it took them to get the Bomb.
The Israeli nuclear chief, Ernst David Bergmann, personally invited Michaels to Israel. Kelly warned Israel might use Michaels as part of a disinformation campaign to show "everything is above board". Michaels was given VIP treatment. He met not only Bergmann but Shimon Peres and Prime Minister David Ben Gurion - the three fathers of the Israeli Bomb.
As Kelly suspected, Michaels' report gave Israel the all clear and he handed it to Hailsham at a crucial time, two days before Ben Gurion met Harold Macmillan at Downing Street.
Tony Benn thinks it inconceivable that Harold Wilson knew of atomic exports to Israel
In 1962 the Dimona reactor started turning uranium into plutonium, thanks to the heavy water Britain had delivered, but Michaels continued to protest Israel's innocence.
Then at the beginning of 1966 UK Atomic Energy Authority made what they remarkably called a "pretty harmless request". They wanted to export 10 milligrammes of plutonium to Israel. The MoD strongly objected and Defence Intelligence wrote directly to say the sale might have "significant military value".
The Foreign Office told UKAEA "It is HMG's policy not to do anything which would assist Israel in the production of nuclear weapons" and therefore they blocked the sale.
Michaels wrote angrily "to protest strongly" against the decision. Five years earlier he had noted such a sale could speed up the Israeli bomb programme, now he was powerfully advocating just that. He said small quantities of plutonium were not important and anyhow if we didn't sell it to the Israelis someone else would. The Foreign Office gave in and the sale went ahead. Kelly believes Mike Michaels knew all along that Israel was after the Bomb. He died in 1992.
Tony Benn is incredulous that Michaels never referred the Israeli nuclear sales to him or Frank Cousins. They were after all the ministers in charge of Britain's nuclear industry including imports and exports. "Michaels lied to me. I learned by bitter experience that the nuclear industry lied to me again and again".
The atomic files, which have been classified until now, detail hundreds of nuclear deals with Israel flagged up as sensitive.
Benn's initial reaction to whether Harold Wilson knew about atomic exports to Israel was "it's inconceivable". Then he muses: "Harold was sympathetic to Israel," before concluding that this was probably a conspiracy by civil servants and the nuclear industry to flout HMG policy.
This report was shown on Newsnight on Thursday, 9 March, 2006.