Northrop Grumman Corp. is eyeing a Japanese jet fighter project that could pit it against Lockheed Martin Corp. three sources said, almost three decades after it lost a similar competition to build an advanced stealth jet for the U.S. Air Force.

"Northrop is interested," said one of the sources, who has direct knowledge of the plans. Northrop has already responded to Japanese requests for information (RFI) and has held preliminary talks with defense industry officials, he said.

Northrop Grumman has provided Japan with a menu of technologies it could contribute to the next-generation F-3 fighter project, but not yet made any specific proposals, the sources said.