TOKYO (Reuters) -Japan and the United States will study steps to jointly develop rare earth mining in the waters around Minamitori Island in the Pacific, Japanese Prime Minister Sanae Takaichi said on Thursday.

Co-development of rare earth minerals was a key topic in her meeting with U.S. President Donald Trump last week, Takaichi told a parliamentary session.

In January next year, Japan will begin test mining for rare-earth-rich mud from the deep seabed off Minamitori Island some 1,900 kilometres (1,180 miles) southeast of Tokyo, in a bid to secure stable supplies amid tightening export controls by China.