North Korea's intentions were not immediately confirmed, while observers viewed the move as aimed at putting pressure on Seoul in the wake of an unsuccessful summit between Pyongyang and Washington in Hanoi in late February.

South Korea is cautious about resuming full-fledged economic cooperation with the communist neighbor amid a lack of substantive process in denuclearization talks and sanctions relief.

While the North has withdrawn its workers from the liaison office, it has allowed South Koreans to continue to work there.

Water and electricity supplies remain intact as well. The North provides the water from its main reservoir in Gaeseong and the South provides the electricity. North Korea's state-controlled media have kept mum about the liaison office issue.

Experts said this suggests Pyongyang does not intend to ruin the reconciliatory mood between the two Koreas itself.

"Given the history, the North could've just kicked us out, but instead they pulled out themselves. Pyongyang is acting cautiously," Choi Yong-hwan, a researcher at the Institute for National Security Strategy, said. (Yonhap)