South Korean liberal candidate Lee Jae-myung is projected to win next week's snap presidential election, a result that could reorient a major U.S. ally on policies ranging from China to nuclear weapons and North Korea.

South Koreans turned out in record numbers to cast their ballots as early voting kicked off on Thursday, with long lines at many of the country's polling stations ahead of the June 3 snap presidential election.

South Korea is heading to the polls on 3 June to elect their next president in a snap election. Former president Yoon Suk Yeol was impeached and removed from office, after briefly placing the country under martial law in December.