A senior U.S. diplomat will meet newly selected presidential candidates in South Korea this week, ahead of next year's election that will shape the future of relations between the two allies.

U.S. Assistant Secretary of State for East Asian and Pacific Affairs Daniel Kritenbrink was due to arrive in Seoul on Wednesday, with plans to hold separate talks with ruling Democratic Party candidate Lee Jae-myung and Yoon Suk-yeol of the main opposition People Power Party.

While domestic issues such as housing prices are expected to dominate the March 9 election, analysts say the result will also shape South Korea's balancing act between China and the United States, and how South Korea coordinates with its U.S. ally on North Korea.