Manfred (Moses) Stern (also known as Emilio Kléber, Lazar Stern, Moishe Stern, Mark Zilbert) (1896–1954) was a member of the GRU, Soviet military intelligence. He served as a spy in the United States, as a military advisor in China, and gained fame under his nom de guerre as General Kléber, leader of the International Brigade during the Spanish Civil War.