"At the moment there are some types of technology and information we're not comfortable sharing while some issues can be worked out. Those issues are being worked out in a bilateral fashion," said Lawrence DiRita, the Pentagon spokesman.

Asked whether the issue was over what other countries Israeli might share the information with, DiRita said, "That's a concern. The question is what can we share with Israel, and there is some information and technology that we're not while we work this out."

DiRita would not say whether the United States was specifically concerned about Israeli arms sales to China, but the move comes amid reports that Washington suspects Israel of upgrading radar hunting Harpy drone that it sold to China.

Israel is a partner in the development of the Joint Strike Fighter, along with a number of other countries.

DiRita said Israel is still a partner in the program, and the United States remains committed to selling it the aircraft in the future.