An 85-year-old former U.S. Army mechanical engineer has pleaded guilty to conspiracy, admitting that he passed classified documents to the Israelis in the 1970s and '80s.

Ben-ami Kadish entered the plea Tuesday in federal court in Manhattan. Kadish said he believes he was promised that the government will not seek imprisonment at his February sentencing.

A prosecutor says the government has agreed it will not oppose a sentence that calls for no jail time.

Kadish pleaded guilty only to one of the four charges of conspiracy he originally faced.

Kadish was accused of taking home classified documents from 1979 to 1985 when he worked at an Army base in New Jersey. The government said he let an unidentified Israeli agent photograph them in his basement. Those documents included information about nuclear weapons.