Pakistani nuclear expert AQ Khan was not arrested when living in the Netherlands as the CIA was monitoring him, an ex-Dutch prime minister says.
Pakistan pardoned AQ Khan, despite his dramatic revelations
Ruud Lubbers said the CIA had asked the Netherlands in 1975 not to prosecute Abdul Qadeer Khan, who is now dubbed the father of Pakistan's atom bomb.
Mr Khan admitted last year that he had leaked nuclear secrets to North Korea, Libya and Iran.
He came under suspicion while working for a Dutch uranium firm, Urenco.
He has been under close guard at his home in Islamabad since his public confession.
According to Mr Lubbers, US intelligence wanted to find out more about Mr Khan's contacts while he was working as an engineer at the top secret Dutch uranium enrichment plant at Almelo.
"The Americans wished to follow and watch Khan to get more information," he told Dutch radio.
Mr Khan returned to Pakistan in 1976 to set up the country's nuclear weapons programme.
He was convicted in absentia of nuclear spying in the Netherlands in 1983, but the conviction was overturned on a technicality.