A top presidential official of the Republic of Korea (ROK) arrived in Washington on Wednesday to discuss with U.S. officials the trade spat with Japan and nuclear talks with the Democratic People's Republic of Korea (DPRK).

The unannounced visit by Kim Hyun-chong, deputy chief of the presidential National Security Office of ROK, comes amid spiking tensions between Seoul and Tokyo after Japan tightened controls on high-tech exports.

Speaking to reporters at Dallas International Airport, Kim confirmed there are many issues to discuss with U.S. officials with the trade spat being the main topic.

When asked "Will you request U.S. mediation on Japan's trade restrictions?" Kim said "That issue will be discussed, too. Certainly."

Kim Hee-sang, director-general for bilateral economic affairs of ROK Foreign Ministry, also landed in Washington on the same day and said to have plans to meet Roland de Marcellus, acting deputy assistant secretary of the U.S. State Department for international finance and development. In the meeting, he intends to explain the unfairness of Japan's action.

The ROK presidential official also said nuclear talks with DPRK will also be discussed during his trip to the U.S. and that DPRK is expected to resume denuclearization negotiations in the coming days.

DPRK’s latest criticism of ROK's military acquisition as an “extremely dangerous action which will trigger our reaction” comes at a time when inter-Korean relations have stalled.

A statement made public by DPRK state news agency, KCNA, on Thursday, said that ROK's acquisition of U.S. F-35 stealth fighter jets will force the DPRK to develop and test "special armaments" to destroy the new weapons.

ROK received the first two F-35 jets in March, with more slated to arrive this year. It has agreed to buy a total of 40, the last to be delivered by 2021. 

"There is no room for doubt that the delivery of 'F-35A', also called an 'invisible lethal weapon', is aimed at securing military supremacy over the neighboring countries in the region and especially opening a 'gate' for invading the north in time of emergency on the Korean Peninsula " the statement said.

(Cover: File photo: Kim Hyun-chong, deputy chief of the presidential National Security Office of ROK. /AFP Photo)

(With input from agencies)