A senior U.S. Defense Department official expressed hope Wednesday that the United States will hold trilateral ministerial talks on defense with Japan and South Korea in Singapore.

Mark Lippert, chief of staff for the U.S. defense secretary, told a symposium that the three countries should build on their success in holding a summit and a senior working-level meeting earlier this year despite tense Tokyo-Seoul ties.

Lippert said he hopes the three defense chiefs can "make sure that things were on track" by getting together on the sidelines of the Asian security forum from May 30 to June 1 in Singapore.