U.S. Vice President Mike Pence and Japanese leaders have begun talks expected to focus largely on trade with America's anchor ally in the region, though tensions with North Korea loomed large.
Pence told business leaders before leaving Seoul that the Trump administration is reviewing all trade agreements as part of its "America First" policy.
Pence reassured Prime Minister Shinzo Abe that the US considers its alliance with Japan to be a cornerstone of security in the region.
Pence struck a stern tone as he began talks with Abe and other Japanese leaders after arriving at a US naval base from South Korea.
"We appreciate the challenging times in which the people of Japan live with increasing provocations from across the Sea of Japan", Pence said.
"We will work with you [to] reform KORUS in the days ahead", he told about 100 USA and South Korean business representatives gathered for his remarks.
The Trump administration has signaled a more forceful USA stance toward North Korea's recent missile tests and threats, including a warning from Trump that North Korean leader Kim Jong Un has "gotta behave". North Korea's nuclear and missile development dominated the agenda on his first stop in South Korea.
A senior North Korean official said Monday that the USA has "created a unsafe situation in which a thermonuclear war may break out at any minute".
Trump also vowed to renegotiate existing trade deals to focus on bilateral agreements rather than regional ones.
Wang told reporters that although USA officials have made clear that a military strike remains on the table, he believes that Washington would still prefer to de-escalate tensions through multi-sided talks.
Pence's meeting in Seoul with business leaders comes before he heads to Tokyo later on Tuesday, where he will meet Japan's Finance Minister Taro Aso and kick off talks that Washington hopes will open doors for US-made products.
US President Donald Trump has vowed to narrow big trade deficits with nations like China and Japan, saying he would boost USA manufacturing jobs.
It is the top US state for per-capita foreign direct investment from Japan, including higher-technology and better-paying manufacturing jobs, said Victor Smith, Pence's commerce secretary when he led the state.
As talks began Tuesday, Aso said the U.S. -Japan alliance has underpinned peace and prosperity in the Asia-Pacific region and that trade friction with the U.S. has given way to an "age of cooperation".
Pence said the USA trade deficit has more than doubled in the five years since the U.S.
But the meetings could indicate how forcefully the US will pressure Japan to further open its farm and automotive sectors.
The loss of USA participation in the TPP was a blow to Japan following strenuous negotiations, especially over opening access wider to its long-protected farm sector.