An 85-year-old former U.S. Army engineer on Tuesday admitted he passed classified documents to the Israelis in the 1970s and 1980s.

Kadish said he believes he was promised that the government will not seek imprisonment at his February sentencing. Assistant U.S. Attorney Iris Lan said prosecutors promised only that they would not oppose or challenge a sentence that included no prison time.

Kadish, a U.S. citizen who lives in New Jersey, pleaded guilty only to one of the four charges of conspiracy he originally faced during his trial in Manhattan.

He had been charged with slipping classified documents about nuclear weapons, fighter jets and air defense missiles to an Israeli Consulate employee who also received information from convicted spy Jonathan Pollard, who was arrested during the same time period, authorities said.

He was accused of taking home classified documents from 1979 to 1985, when he worked at the Armament Research, Development and Engineering Center at the Picatinny Arsenal.

The government said he let the Israeli agent photograph documents, including information about nuclear weapons, a modified version of an F-15 fighter jet and the U.S. Patriot missile air defense system.

Prosecutors said it appeared that Kadish, who was born in Connecticut but was raised in Palestine pre-1948, was motivated by a desire to help Israel.

The judge asked Kadish if he obtained the classified documents from the library of the Picatinny Arsenal and supplied them to Yossi Yagur, the Israeli government agent who had requested them.

Kadish, who worked there from 1963 to 1990, said he had.

The judge also asked if Kadish requested anything of value or received anything of value for the classified documents.

Kadish said he did not. He admitted that he provided the documents for the benefit of Israel.

Yagur, now retired and living in Tel Aviv, is the agent who obtained information from convicted Pentagon spy Jonathan Pollard, who is serving a life sentence for selling military secrets to Israel while working as an intelligence analyst for the Navy. Pollard's case damaged U.S.-Israeli relations and remains a sore point between the countries.

U.S. authorities say Kadish confessed to FBI agents that he had given Yagur between 50 and 100 classified documents and accepted no cash in return, only small gifts and occasional dinners for him and his family.

Kadish had told the FBI that he knew that one restricted document he provided to the agent included atomic-related information and that he did not have the required clearance to borrow it, according to a criminal complaint filed in the case.

Alon Pinkas, Israel's former New York consul, said in April the charges against Kadish might have been announced to prevent the release of Pollard, whose case remains a blot on otherwise close relations between the countries.

The link between Pollard and Kadish is a now-defunct Israeli intelligence agency known as the Scientific Relations Office. The office was run by Rafi Eitan, a former agent with Israel's Mossad spy agency who is now a Cabinet minister.

Outside the Mamhattam court on Tuesday, Kadish, asked if he was hopeful the spy case was over, said, "I hope so." His wife told him not to say any more.