After an impeachment vote against South Korean President Yoon Suk Yeol failed on Saturday, opposition lawmakers have accused his ruling party of staging a “second coup” by clinging on to power.

Tens of thousands of people had come out in protest, calling for Yoon’s resignation or impeachment after he shocked the country with a martial law declaration last week.

But the vote to impeach Yoon failed and the ruling People Power Party (PPP) said instead that its party leader and prime minister would run the country until the president’s “orderly exit”.

The move has been criticised as unconstitutional by the opposition Democratic Party, which has vowed to hold impeachment votes against Yoon every Saturday.

In a public address on Sunday, PPP leader Han Dong-hoon said Yoon would no longer be involved in foreign and domestic affairs until his early resignation – adding that Prime Minister Han Duck-soo would manage government affairs in the meantime.

“The President will not be involved in any state affairs including diplomacy before his exit,” said party leader Han.

However, Democratic Party floor leader Park Chan-dae described the proposed plan as “an illegal, unconstitutional second insurrection and a second coup”.

Representative Kim Min-seok of the Democratic Party had similarly criticised the plan, saying “nobody gave” PPP leader Han the power to make such decisions.

“The Prime Minister and the ruling party’s announcement that they would jointly exercise the powers of the president, which no one has given them, is clearly unconstitutional” he said, according to a Korea Herald report.

On social media, many South Koreans voiced their concerns, saying there is a lack of clarity on who is leading the country.

The Ministry of National Defence confirmed at a briefing on Monday that the president retains command of the armed forces. That means in the event of any foreign policy incidents, including any possible threat from North Korea, Yoon is still, in theory, able to make executive decisions.

“The president can take the lead again any time he changes his mind,” political science professor Shin Yul of Myongji University told The Korea Herald.

“No one will be able to stop him, if Yoon insists.”

On Saturday Yoon made his first appearance since the martial law declaration, pledging that he would not impose another martial law order, and apologising for the “anxiety and inconvenience” caused by his declaration.

However, the opposition has insisted that they “will not give up” on impeaching Yoon.

“We will definitely return this country to normal by Christmas and the end of the year and give it to you as a Christmas and end-of-year gift,” Democratic Party leader Lee Jae-myung told a disappointed crowd after Saturday’s failed impeachment attempt.

He again urged Yoon to resign on Monday, telling a press conference that Yoon’s actions were “destroying” South Korea and its economy.

Additional reporting by Yuna Ku in Seoul