South Korea's cabinet is expected to finalise a June 3 date for a presidential election following the removal of Yoon Suk Yeol last week for his short-lived martial law declaration, Yonhap news said on Monday.

Although not required by law, the cabinet will make the decision at a meeting on Tuesday, as it needs to approve a holiday for the event, Yonhap cited an unidentified government official as saying.

RTHK's correspondent in Seoul, Frank Smith, said Lee Jae-myung, leader of the main opposition Democratic Party of Korea (DPK), was considered the frontrunner in a new election, having lost to Yoon in 2022 by a margin of less than one percent.

"He's widely favoured. He's got something like a margin of 34 percent approval to nine percent for the second candidate of the Conservative bloc. So he's looking pretty good. He does have some legal problems, however, that could affect his campaign and possibly even prevent him from running, although he cleared a hurdle in that regard about two weeks ago," said Smith.

Yoon was removed by the Constitutional Court on grounds of having violated his official duty by issuing the martial law decree on December 3 and mobilising troops to halt parliamentary proceedings.

The law requires a new presidential election within 60 days if the incumbent dies or is removed from office.

An official of the National Election Commission said the date mentioned in media reports was not final and would not become official until declared by the acting president, Prime Minister Han Duck-soo.

Smith said he did not think Yoon's removal would be the end of the current political crisis in South Korea.

"South Korea has some serious political divisions that really bubbled to the surface over the past four months. Those are going to remain here. For Yoon, on the legal front, the impeachment is just one aspect of this. He still has a criminal trial to go. His lawyers prioritised the impeachment trial and kind of set aside the criminal trial as much as possible... So he has some pretty serious charges of insurrection to face, again, looking at a long prison sentence and perhaps even a death penalty, although most people suggest that's quite unlikely." (Additional reporting by Reuters)