SEOUL, Oct 22 (Reuters) - Senior South Korean officials

will visit Washington on Wednesday for urgent discussions aimed

at finalising a tariff deal that has been on hold over details

tied to a $350 billion investment, ahead of an Asia-Pacific

summit later this month.

Presidential Policy Secretary Kim Yong-beom and Industry

Minister Kim Jung-kwan, who met U.S. Commerce Secretary Howard

Lutnick last Friday, will reconvene with Lutnick again to iron

out outstanding differences over the large investment pledge.

"Gaps have been narrowed between the two sides on many

issues, but there are a couple of matters over which the two

sides still stand apart," Secretary Kim said before boarding a

flight to Washington.

Kim said he would seek to reach an agreement that is in the

interests of both countries and would not sign any partial deal

solely to meet a deadline.

South Korean officials have said Washington was no longer

insisting on an "upfront" payment of the sum largely in the form

of equity, which Seoul has said would destabilise its foreign

exchange market.

The security allies have expressed optimism about a

breakthrough in the stalled talks as their leaders are expected

to meet on the sidelines of an Asia-Pacific Economic Cooperation

(APEC) summit later this month in South Korea.

Shares of South Korean automakers Hyundai Motor ( HYMLF )

and Kia Corp ( KIMTF ) rallied on Tuesday on hopes of a trade

breakthrough. U.S. tariffs on South Korean cars remain at 25%

pending a final deal, whereas duties on other imports have been

cut to 15%.