Israel is on a list of counterintelligence targets that also includes China, Russia, Iran, Pakistan and Cuba, suggesting the U.S.-Israeli alliance has its tensions, The Hill reported.
The fiscal 2013 "black budget" was first reported by The Washington Post.
"To further safeguard our classified networks, we continue to strengthen insider threat detection capabilities across the Community," the budget said. "In addition, we are investing in target surveillance and offensive CI against key targets, such as China, Russia, Iran, Israel, Pakistan and Cuba."
Both Israel and the United States have a history of spying on each other. Jonathan Pollard, a U.S. citizen who was sentenced to life in 1987 for spying for Israel, remains behind bars.
Paul Pillar of Georgetown University, a former national intelligence officer for the Mideast, told The Hill the two countries' interests are sometimes at odds.
"Everything is trumped by political realities," Pillar said. "Don't expect any statement by the White House press secretary tomorrow that says, 'Oh my gosh, we are really upset with the Israelis for trying to spy on us.' You're never going to hear anything like that, because politically it is hazardous for basically any American politician -- and certainly an incumbent American administration -- to underscore ... the divergence of U.S. and Israeli interests."