Britain and Japan are close to an agreement to merge their next-generation Tempest and F-X fighter jet programs, with the two countries aiming for a deal on a new joint project by year-end, three sources told Reuters.

It would be the first time Japan has sought a non-U.S. partner for a large military program and the first major collaboration between Tokyo and London, going beyond what had been expected when industrial talks began five years ago.

¡°This would be an equal partnership between Japan and Britain,¡± said one of the sources with knowledge of the plan. It will cost tens of billions of dollars, he added.