Japanese and U.S. officials resumed talks Thursday in Tokyo on the proposed Trans-Pacific Partnership Agreement, but the outcome of the negotiations remains unclear with political difficulties mounting for Prime Minister Shinzo Abe and indications of growing opposition to the deal in the U.S.

"We want to do what we can do," chief Japanese negotiator Hiroshi Oe told reporters before the meeting got underway.

The renewed effort to conclude a bilateral agreement on the TPP comes about a month after the last negotiations, in which Tokyo reportedly offered to slash tariffs on beef from the current 38.5 percent to 9 percent over 15 years.