WASHINGTON - A top scientist who worked at Nasa and the Pentagon was arrested yesterday and charged with attempting to pass classified information to what he thought was an Israeli secret agent.

Stewart Nozette, 52, developed an experiment that fuelled the discovery of water on the south pole of the moon, and held a special security clearance at the United States Department of Energy on atomic materials.

He was charged with attempted espionage for knowingly and wilfully attempting to communicate, deliver and transmit classified information relating to someone he thought was an Israeli operative. However, the contact was in reality an FBI officer.

FBI agent Leslie Martell said that on September 3, Nozette received a telephone call from an individual purporting to be an Israeli intelligence officer. Nozette agreed to meet the agent that day at a hotel in Washington and in the subsequent meeting the two discussed Nozette's willingness to work for Israeli intelligence.

Nozette allegedly informed the agent that he had, in the past, held top security clearances and had access to satellite data, court papers said.

He also was alleged to have said he would be willing to answer questions about this information in exchange for money. The affidavit said the agent explained that the Israeli intelligence agency, Mossad, would arrange for a system so Nozette could pass on information in a post office box.

Nozette allegedly agreed to provide regular information and asked for an Israeli passport.

The scientist has worked in varying jobs for the Department of Energy, Nasa and in the National Space Council in the president's office in 1989 and 1990.

He developed a radar experiment that purportedly discovered water on the south pole of the moon.

At the Department of Energy, Nozette held a special security clearance equivalent to the Defence Department top secret and "critical nuclear weapon design information" clearances.He performed some of the research and development at defence and space flight centres.

The FBI stressed the Israeli government was not accused of attempting to gain information from the US.

- AP