Japan and the United States have taken a "step forward" in negotiations over Tokyo's proposal to maintain tariffs on beef and pork under the Trans-Pacific Partnership, but severe hurdles remain, a Japanese trade official said.

Both governments will continue trying to strike a deal, Hiroshi Oe, deputy chief TPP negotiator, said Tuesday after wrapping up two days of talks with his U.S. counterpart, Wendy Cutler.

The Office of the U.S. Trade Representatives released a statement saying both governments "continued to make some progress in narrowing the gaps on treatment of a range of agricultural products."