Five months before voters head to the polls, South Korea’s ruling and main opposition parties have selected their candidates for a presidential election that is expected to have a dramatic impact on Seoul’s ties with Tokyo, as well as the country’s stances on North Korea, China and its alliance partner, the United States.

On Friday, the conservative opposition People Power Party chose former top prosecutor Yoon Seok-youl, 60, as its presidential candidate, while the ruling Democratic Party selected Lee Jae-myung, 56, the former governor of the country's most populous province of Gyeonggi, late last month.

Under South Korean President Moon Jae-in, ties between Tokyo and Seoul plummeted to their lowest point in years over history and trade disputes, with neither Moon nor Prime Ministers Shinzo Abe and Yoshihide Suga willing to budge on the issues.