Speaking by telephone from Israel in a call relayed by loudspeakers to the assembly, Vanunu appealed for the promotion of worlddwide peace and the reduction of inequality between peoples.

"This is a message for the 21st century," he told the European Social Forum, which has attracted 19,000 activists to the British capital this weekend.

Vanunu was sentenced in 1986 to 18 years in prison on charges of treason and espionage after leaking top-secret details about the Dimona nuclear plant to the London newspaper The Sunday Times.

On his release, he was subjected to a series of sweeping restrictions, including a ban on travelling abroad as well as holding unauthorized meetings with foreigners.

"Military budgets must be reduced everywhere," he told a debate on disarmament.

Trade unionists, environmentalists, human rights activists and other delegates from around the world have gathered in London for the three-day European Social Forum.

The hundreds of seminars, debates and workshops during the forum will see virtually every left-leaning, anti-corporate and pro-green subject covered, although concern at the situation in Iraq has threatened to dominate proceedings.

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