Japan will agree this month to give Australia classified submarine data, an unprecedented step signaling Tokyo¡¯s intent to join competitive bidding to sell Canberra a fleet of stealth subs, said two Japanese officials familiar with the plan.

The ¡°competitive assessment¡± will see Germany¡¯s ThyssenKrupp and France¡¯s state-controlled naval contractor DCNS separately competing with a Japanese government-led bid for such contractors as Kawasaki Heavy Industries Ltd. and Mitsubishi Heavy Industries Ltd.

Japan had been the front-runner in the planned sale of around 12 vessels, for as much as $40 billion, to replace Australia¡¯s ageing Collins class submarines, sources have said, until Prime Minister Tony Abbott opened up the bidding under pressure from opposition and ruling party lawmakers.