Exclusive - Japan seeks to sell sub-hunting jet to UK as Abe pushes arms exports

A Japan Maritime Self-Defense Forces P-1 submarine-hunting aircraft, manufactured by Kawasaki Heavy Industries, is seen in this undated handout photo released by the Japan Maritime Self-Defense Forces, and obtained by Reuters on January 7, 2015. REUTERS/Japan Maritime Self-Defense Force/Handout via Reuters

TOKYO (Reuters) - Japan is asking Britain to buy its P-1 submarine-hunting jet in a deal that could top $1 billion (660 million pounds), a major step in Prime Minister Shinzo Abe's push to arms exports after decades of self-imposed restrictions, people with knowledge of the proposal said.

Britain has not formally decided it will buy new maritime patrol planes, having cancelled an order for nine built by BAE Systems in 2010 due to delays and cost over-runs, and the P-1, made by Kawasaki Heavy Industries <7012.T>, would face stiff competition from Boeing's P-8 Poseidon, the three sources told Reuters.