Defence Minister Shaul Mofaz and Justice Minister Tommy Lapid were meeting with Attorney General Meni Mazuz over ways of keeping the unrepentant whistleblower from divulging more of Israel's military secrets when he is released in just under two months' time, the radio said.

Secret service officials, trying to uncover Vanunu's plans on release, spent three hours with him in his cell in Shikma prison in the southern port town of Ashkelon earlier on Tuesday, the radio said.

There was no official confirmation of the report.

Last week, Parliamentary Relations Minister Gideon Ezra said the secret service could hold Vanunu in administrative detention "to keep him from divulging secrets."

Israeli authorities can detain a suspect in administrative detention for renewable periods of six months without charges or trial. It is a practice frequently used to detain suspected Palestinian militants.

Vanunu, 49, worked as a technician at the Dimona nuclear facility in southern Israel. He was sentenced to 18 years in prison in 1986 after giving details about Israel's secret weapons programme to Britain's Sunday Times.

Israeli agents lured Vanunu from London to Italy, where he was kidnapped and brought to Israel. He was tried in secret and found guilty of "espionage".

He is due to be released from prison on April 21.

Israel has firmly adhered to a policy of "nuclear ambiguity", never confirming or denying it possesses nuclear weapons. But foreign experts believe the Jewish state holds at least 200 atomic warheads.

WAR.WIRE