The British Broadcasting Corporation reported that two British lawmakers accused the British government of covering-up a secret deal under which the UK helped Israel in launching its nuclear program in 1959.

The deal included secretly selling a batch of heavy water which is considered a key ingredient in producing weapons-grade materials.
The British Broadcasting Corp. first reported on the deal, in August, and presented previously classified documents, but the UK Foreign Office minister Kim
Howells denied the report to the International Atomic Energy Agency.
UK lawmaker Menzies Campbell, foreign affairs spokesman from the small centrist Liberal Democrat party told the BBC’s Newsnight program, late o Friday at night, said that the statements of Howell “simply fly in the face of known facts, we now have access to documents which were classified previously”.
Meanwhile, Jeremy Corbyn a lawmaker from the governing Labor Party demanded a committee to investigate the reports, adding that the statements of Howell are “simply untrue”.
“The documents which were classified revealed that 20 tons of heavy water were part of a delivery that Britain brought from Norway but later decided was surplus to requirements”, Israeli online daily Haaretz reported.
Also, the document shows how officials presented the transaction as a straight sale which was shipped from a British port into Israeli ships. In two shipments of heavy water; half of the amount was transferred in June 1959 and half a year later.
The UK Foreign Office did not give immediate comments on the report.
Heavy water is the key to one type of reactor in which plutonium can be bred from natural uranium. As such, the production of heavy water has always been monitored, and the material is export controlled.
In addition, a source of deuterium is essential for the production of tritium and 6LiD, two ingredients of thermonuclear weapons. A nation seeking large quantities of heavy water probably wishes to use the material to moderate a reactor, and may be planning to produce plutonium. However, CANDU (Canadian Deuterium Uranium) reactors designed and built in Canada are used for commercial electric power production.
Heavy water, D2O, is water in which both hydrogen atoms have been replaced with deuterium, the isotope of hydrogen containing one proton and one neutron. It is present naturally in water, but in only small amounts, less than 1 part in 5,000. Heavy water is one of the two principal moderators which allow a nuclear reactor to operate with natural uranium as its fuel. The other moderator is reactor-grade graphite (graphite containing less than 5 ppm boron and with a density exceeding 1.50 gm/cm 3). The first nuclear reactor built in 1942 used graphite as the moderator; German efforts during World War II concentrated on using heavy water to moderate a reactor using natural uranium.
The importance of heavy water to nuclear proliferators is that it provides one more route to produce plutonium for use in weapons, entirely bypassing uranium enrichment and all of the related technological infrastructure. In addition, heavy-water-moderated reactors can be used to make tritium.