Visiting US officials Monday discussed the issue of North Korea with their South Korean counterparts.
Assistant Deputy Secretary of State Daniel Russel and Assistant Deputy Secretary of Defence David Shear arrived in Seoul Sunday, Xinhua reported.
They held talks with South Korean Deputy Foreign Minister for Political Affairs Lee Kyung-soo at the headquarters of Seoul's foreign ministry.
Their visit came after North Korea's second-in-command Hwang Pyong So made a surprise visit Saturday to South Korea for the closing ceremony of the Incheon Asian Games along with Choe Ryong Hae and Kim Yang Gon, secretaries of the Central Committee of the Workers' Party of Korea.
Russel said the US supported South Korea's efforts to strengthen and promote inter-Korean relations as well as relations between Seoul and Tokyo.
Russel and Shear visited Seoul before flying into Tokyo to discuss a revision of the US-Japan defence cooperation guidelines.
