The Japanese government wants Australia to explain why it decided not to pick a Japanese design for a new fleet of submarines, choosing instead a proposal from France's DCNS.
"The decision was deeply regrettable," said Japan Defence Minister Gen Nakatani on Tuesday. "We will ask Australia to explain why they didn't pick our design."
Australian officials informed Japan of its choice on Monday, explaining that the French design best fitted its unique needs, Nakatani said.