LONDON, March 12 (Xinhuanet) -- Britain has been secretly designing a new nuclear warhead with the United States, triggering off a legal row over the proliferation of nuclear weapons, the Sunday Times reported.

    According to the report, the government has been pushing ahead with the program while claiming that no decision has been made on a follow-up to Britain's Trident nuclear deterrent, estimated to have cost nearly 10 billion pounds (some 17.4 billion U.S. dollars).

    Scientists at the Atomic Weapons Establishment at Aldermaston in South Britain have been working on a new weapon since British Prime Minister Tony Blair was re-elected last May, and is now said to be ahead of similar U.S. research, the report claimed.

    The aim is to produce a simpler device using proven components to avoid breaching the ban on nuclear testing. Known as the Reliable Replacement Warhead, it is being designed so that it can be tested in a laboratory rather than by detonation. Enditem