South Korea's Constitutional Court dismissed the impeachment of Prime Minister Han Duck-soo Monday, reinstating him as acting president — a role he was given after the president was suspended for declaring martial law.

"Han's impeachment was dismissed in a 5-1 vote by the court's eight justices. Two justices voted to reject the impeachment motion entirely," Yonhap reported.

The court ruling is the latest development in South Korea's complex and sprawling political crisis, which was touched off by suspended President Yoon Suk Yeol's December 3 attempt to subvert civilian rule.

The opposition-controlled parliament impeached Yoon's replacement Han just weeks after he assumed the role.

Lawmakers cited Han's refusal to appoint more judges to the Constitutional Court — which will also decide on Yoon's impeachment — plus his purported role in the martial law debacle.

The court only had six judges at the time, meaning that had even one judge refused to back impeachment, Yoon would have been reinstated. The opposition had called for three more to be appointed, taking the court up to a full bench.

According to local broadcaster YTN, the court decision on Monday "explained that not certifying nominees is illegal, but not enough to warrant dismissal," in its decision to throw out Han's impeachment.

YTN also said that the court "found no evidence of (Han's) role" at meetings related to planning the martial law declaration.

Han's successor as acting president, Choi Sang-mok, appointed two additional judges to the Constitutional Court.

Han, who immediately resumed the acting presidency after the ruling, thanked the Constitutional Court for its "wise decision."

"I believe that all citizens are clearly speaking out against the highly polarized political sphere. I think there is no place for division now. Our country's priority is to move forward," he added.

Yoon impeachment ruling

The court's decision was closely watched as it comes ahead of a highly anticipated ruling on suspended president Yoon's impeachment, the date of which has not yet been announced.

At least six of the eight justices must vote to remove Yoon. Otherwise, he will be reinstated.

Despite experts predicting a verdict on that case by mid-March, the Constitutional Court has yet to rule, making Yoon's case the longest deliberation in its history.

Yoon was suspended by parliament in December, and arrested in January in a dawn raid in connection to a separate criminal investigation on insurrection charges, which are not covered by presidential immunity.

He is the first sitting South Korean president to stand trial in a criminal case.

He was released from detention in early March on procedural grounds — a move that has appeared to invigorate his supporters.

Hundreds of thousands of South Koreans took to the streets over the weekend, as rallies for and against Yoon intensified ahead of the court verdict.