Mordechai Vanunu, who served 18 years in prison after he revealed Israel's secret nuclear programme, has been placed under house arrest pending criminal charges for allegedly breaching the terms of his 2004 release, which includes a ban on contacts with foreigners.

A police spokesman, Micky Rosenfeld, said Vanunu was accused of meeting with "a number of foreigners". The spokesman, however, did not specify who the foreigners were or where they came from.

Vanunu's lawyer, Avigdor Feldman, said his client had been arrested because his romantic attachment to an unnamed Norwegian woman had come to the attention of the authorities.

"Vanunu was arrested [for] a relationship between a man and a woman, with a Norwegian citizen," he told Reuters. "He is not being accused of giving any secrets. She is not interested in nuclear business – she's interested in Mordechai Vanunu [and he] is probably interested in her."

The woman has reportedly been interrogated by police but has not been charged with any offence.

Vanunu has fallen foul of the no-foreigners rule before. In 2007, he was sentenced to six months in jail for talking to non-Israelis.

Vanunu, a former technician at Israel's Dimona nuclear plant, was first jailed in 1986 after he passed on information about Israel's nuclear programme to the Sunday Times. The Israeli authorities argue that he may have kept back some information which could still be of use to a hostile foreign power.

His dilemma is compounded by the fact that most Israelis do not approve of his actions and want no contact with him. Vanunu says the feeling is mutual and he would prefer to live abroad, but is banned from doing so.

Israel's supreme court has upheld the restrictions on his freedom of association and movement despite criticism by international human rights groups.

Speaking in court today, Vanunu – who refuses to speak Hebrew publicly in protest at his treatment – said: "This Jewish state has 200 atomic ... hydrogen bombs, atomic weapons, neutron bomb. They are not able to say they have the bomb, they are not able to destroy anyone ... instead they arrest Vanunu."

After talking to the Sunday Times, Vanunu was tracked down in Rome where he was kidnapped by Israeli intelligence agents and brought back to Israel to stand trial.

Israel has never publicly acknowledged its nuclear weapons arsenal.