A Japanese government team is in talks with at least two top British firms to help a Japanese consortium land one of the world's most lucrative defense contracts, sources in Tokyo said, a $50 billion project to build submarines for Australia.

Germany's ThyssenKrupp (TKMS), a rival bidder, is wooing anxious members of Prime Minister Tony Abbott's ruling Liberal Party with the economic and political benefits of its proposal.

Two Japanese government officials and a company source in Tokyo said Babcock International Group and BAE Systems had approached the consortium of Mitsubishi Heavy Industries and Kawasaki Heavy Industries with offers of help. Other British defense contractors may also be involved, they said.