A U.S. space scientist has pleaded guilty to attempted espionage for trying to sell classified information to a U.S. federal agent posing as an Israeli intelligence officer.

The Department of Justice said Wednesday that Stewart David Nozette entered his plea Wednesday in federal court in Washington, D.C. Federal officials and Nozette's lawyers agreed to a 13-year prison sentence in exchange for the plea. He is to be formally sentenced later this year.

Nozette was arrested in 2009 after he tried to sell information to an F.B.I. agent posing as an Israeli intelligence officer. The Department of Justice says Nozette's indictment does not implicate Israel or anyone acting on Israel's behalf.

Nozette, a planetary sciences specialist, worked for various federal agencies including the Department of Energy, the U.S. space agency NASA, and the Department of Defense. He also served on the White House National Space Council.