Talks with the United States aimed at narrowing remaining differences over a Pacific free trade pact resumed Monday in Tokyo.

Officials from all 12 negotiating members are gathering in Canada later this week.

The two biggest economies in the Trans-Pacific Partnership framework will discuss tariffs on Japan's key farm products and trade barriers in the auto sector — the biggest sticking points — during the three-day working-level talks.

The focus is on whether the two sides can resolve differences on tariffs and safeguards on imports of beef and pork, one of Japan's five off-limits farm product categories, people involved in the negotiations said.

Japan is considering drastically reviewing tariffs on U.S. beef and pork, but it wants to introduce safeguards should imports of the products surge under the TPP. Tokyo and Washington have yet to agree on the details, the officials said.

The latest round of Japan-U.S. talks comes in the run-up to a plenary TPP meeting from Thursday in the Canadian capital of Ottawa, which trade observers say will be a crucial session for an early conclusion of the pact.

Whether a ministerial meeting, which usually follows working-level talks, takes place later depends on progress in Ottawa, Akira Amari, Japan's minister in charge of the TPP, has said.

Last month, U.S. President Barack Obama, who has put the TPP at the core of his strategic shift to Asia, said Washington envisions the 12 countries producing a document on the initiative in time for his trip to Asia in November.