The United States is keen to "nail down" a trade deal with South Korea as soon as Seoul is willing to take "appropriate" commitments, a senior US official said Friday, as the two countries strive to bridge differences over how to implement Korea's $350 billion investment pledge under the framework deal.

The official made the remarks during an online press briefing amid uncertainty over whether Seoul and Washington could reach a breakthrough to finalize details of the trade deal before or during a summit between Korean President Lee Jae Myung and US President Donald Trump, set for Wednesday in Korea.

Trump is set to pay a two-day state visit to Korea on Wednesday and Thursday, as Korea will host the Asia-Pacific Economic Cooperation summit in the southeastern city of Gyeongju on Oct. 31 and Nov. 1.

"We are very keen to nail down a deal with Korea as soon as possible, as soon as they're willing to take the commitments that we think are appropriate," the official said.

The official reaffirmed the Trump administration's interest in shipbuilding cooperation with South Korea.

"We welcome their know-how, their capital and ... the general collaboration to help America revive its manufacturing, defense industry, shipbuilding and submarine building."

The two countries reached their trade deal in late July, under which Seoul committed to investing $350 billion in the US, among other pledges, in return for Washington's agreement to lower its "reciprocal" tariff and sector-specific duty on South Korean autos to 15 percent from 25 percent.

But the deal has yet to take effect amid negotiations to reconcile differences over a series of sticking points, including how to fund the investment package.

In recent weeks, top South Korean officials, including Kim Yong-beom, the presidential chief of staff for policy, Finance Minister Koo Yun-cheol and Industry Minister Kim Jung-kwan, have visited Washington multiple times, underscoring Seoul's stepped-up efforts to reconcile differences over sticking points in the trade talks. (Yonhap)

US keen to 'nail down' trade deal with S. Korea as soon as possible: senior official