Japan brought its submarine-hunting aircraft to a British air show Friday, signaling its intention to compete for a potential multibillion-dollar contract.
Britain has not formally decided it will buy new maritime patrol planes but is under pressure to do so to ensure it can carry out aerial hunts for submarines after retiring a former program in 2011.
A U.K. government defense and security review due to conclude later this year could state the need for a new maritime patrol force to replace the Nimrod, which tracked Soviet undersea activity during the Cold War.
Kawasaki Heavy Industries' P-1 is one contender. Boeing could offer its P-8 Poseidon, and Airbus has an option based on its C-295 military aircraft.
After decades of restraint under a pacifist Constitution, Japan is starting to try to export more arms.
The P-1 was due to fly at the Royal International Air Tattoo in central England on Saturday, the first time a Japanese military plane has participated in a European flying display.
A spokesman for the Air Self-Defense Force told reporters Friday that it is up to Britain to decide on the P-1's suitability for any requirements it might have.
Britain's decision comes at a time of rising tensions with Russia. Royal Air Force fighter jets have been scrambled to intercept Russian long-range bombers in recent months, and there have also been reports of suspected submarines in Swedish and Finnish waters, fueling regional concerns.