The session has begun with the opposition Democratic Party's parliamentary floor leader Park Chan-dae, who introduces the impeachment bill.

"At 22:30 on 3 December, the heart of democracy stopped," he said, in reference to Yoon's martial law declaration. He added that it reminded him of martial law during the 1980 Gwangju protests, a landmark event in South Korean history that saw violent clashes and left many dead.

Following the entrance of PPP members, the speaker of the National Assembly has announced the session has begun.

"I hope every one of you will participate in the vote," says Speaker Woo Won-shik.

MPs from the six opposition parties, whose coalition is the majority in the National Assembly, have entered the chamber for the vote now.

Stay with us for updates - the vote is imminent.

The general meeting of the ruling People Power Party has ended after about six hours.

A party spokesperson tells reporters that the party will participate in the impeachment vote now. This represents an about-face from last Saturday, when the party boycotted the first impeachment vote .

While the party's official stance remains opposed to Yoon's impeachment, party leader Han Dong-hoon has told members to vote according to their "conscience".

We're just minutes away from the vote taking place in the National Assembly, and President Yoon is likely to be watching the results from his official residence in Hannam-dong, Korean media reports.

If the impeachment motion is passed, he will be immediately suspended from his duties.

The vote is also likely being closely watched by the office of South Korean Prime Minister Han Duck-soo, since Han will immediately assume the role of acting president if the vote passes.

According to local media reports, several senior staff members from his team went to work this morning.

Image source, Getty Images

Richard Kim
BBC Korean reporter

As the impeachment vote approaches, ruling party lawmakers are still in their marathon meeting, while members of the main opposition Democratic Party (DP) have gathered on the steps of the rotunda outside the main chamber, chanting in support of the impeachment motion.

Supporters cheered and applauded as DP leader Lee Jae-myung entered the National Assembly building, chanting his name.

DP lawmaker Kim Byung-joo, told the BBC he believes the impeachment motion will succeed today, saying "it is the will of the people".

Meanwhile, the Justice Party, a minor opposition party, held a press conference, calling for the immediate arrest of President Yoon and urging support for the impeachment.

Image source, BBC/Richard Kim

Suhnwook Lee & David Oh
BBC Korean Service reporters

Among the thousands gathered today in front of the National Assembly are many mums and dads with young children.

They have a unique shelter provided for them: the Kids Bus.

One mum, who had originally planned to use a bus for a trip with her two-year-old daughter Jiwoo, decided to repurpose the vehicle to provide a temporary shelter for children and parents.

“I was at a rally previously but found it difficult to change diapers and feed my child,” she explains. So she took it upon herself to set up this space. With support from citizens, the number of buses grew to three, and donations of diapers, formula, snacks, and other supplies poured in.

Park Hyun-jung, who used the Kids Bus at the rally, said: “Thanks to it, I was able to change diapers and escape the cold.”

President Yoon's approval rating has tumbled to a record low of 11%, a poll showed on Friday, down from 13% a week ago.

The poll by Gallup Korea surveyed over 1,000 adults. Three in four of them said they support the president's impeachment, up from 73% in last week's poll.

Negative assessment of Yoon rose to a record high of 85% among respondents, with at least half citing his short-lived martial law attempt as a reason for their assessment.

Koh Ewe
Live page reporter

Their call for Yoon's impeachment may be serious, but protesters have not shied away from showing their irreverent side. Many have showed up with quirky flags representing fictitious associations.

The popularity of such flags is said to have started during the 2016 protests against former president Park Geun-hye. At that time, critics cast doubt on protesters, arguing that they did not belong to major political organisations - which inspired protesters to invent their own associations.

Here are some of the best ones seen by our reporters Jake Kwon and Leehyun Choi in Seoul today:

Image source, BBC/Jake Kwon

Image source, BBC/Jake Kwon

Image source, BBC/Jake Kwon

The BBC also saw a man who identified himself as a representative from the "National Coalition of People Who Want to Stay Lying Down".

"Don't you all want to finish this quick, go home, and lie down?" he shouted to a cheering crowd. "We can't wait to go back home and lie down. But we're here today committed to see President Yoon impeached."

Image source, BBC/Jake Kwon

Yuna Ku
BBC Korean

Image source, BBC/Yuna Ku

Protesters at a pro-Yoon rally are forming a long line from Gwanghwamun to Seoul's City Hall. Some 30,000 participants are expected to show up, according to reports.

“Save President Yoon," some people are chanting, "Get rid of North Korean sympathisers". Others have also called for the arrest of opposition leader Lee Jae-myung.

Most of the protesters are elderly, but I have also seen several young people among them.

When I was on the subway earlier, an old man could be heard shouting inside the train, “The impeachment bill should be rejected. That’s for our country.”

Image source, BBC/Yuna Ku

Net closing in on Yoonpublished at 06:18 Greenwich Mean Time

06:18 GMT

Jean Mackenzie
Seoul correspondent

For a short while this week, it looked as if Yoon had struck a deal with his party to stand down early, in return for them not booting him out of office in last weekend's vote.

But as the week sped by, there was no sign of the president nor the details of such a plan, and it gradually became obvious Yoon had zero intention of resigning.

Meanwhile, the roars of anger from the thousands of people on the street every night are getting louder.

Within the week, the president has morphed from being contrite and apologetic, hoping to avoid impeachment, to brazenly defiant, vowing to fight on as the net closed in on him.

Read more analysis from our Seoul correspondent here.

Korean pop idol IU has sponsored food and hand warmers for fans taking part in the rallies, according to reports.

Her agency said hundreds of snacks and drinks were available for pick up across five different cafes near the National Assembly.

Meanwhile Yuri, a member of the massively popular girl group Girls Generation, has also prepared food for her fans.

One cafe in front of the National Assembly is offering free drinks, as well as shelter to protesters in need of a reprieve from the cold.

Words of encouragement have been posted in the signs in yellow, with one phrase calling on protesters to "do their best".

Image source, Reuters

Image source, Reuters

Just a reminder, this is the second time South Korean MPs are trying to impeach the president.

Exactly one week ago, similar scenes of protest played out in front of the National Assembly as lawmakers voted on an impeachment bill against President Yoon.

Yoon narrowly survived that impeachment attempt after most lawmakers from his party boycotted the vote. While some ruling party members stayed for the vote, they still fell five votes short of the number needed to impeach Yoon.

Parliament is back at square one today. But things may be different now. Over the past week, more lawmakers from Yoon's party have signalled their intention to vote in favour of impeachment.

Party leader Han Dong-hoon has urged members to vote according to their "conscience", saying that impeachment was the "one effective method" to stop Yoon.

Image source, Getty Images

The city is seeing a flurry of activity today, as protesters - both supporting and against the president - stage huge rallies ahead of the impeachment vote this afternoon.

Image source, Getty Images

Image source, Reuters

Image source, Reuters

Image source, Getty Images

Yoon's People Power Party (PPP) has been in a general meeting since 10am local time, according to the Yonhap news agency. Members appear to be struggling to arrive at a consensus on the party's official stance regarding the impeachment vote.

Earlier this week, the party elected Yoon-loyalist Kwon Seon-dong as its new floor leader. Kwon has spoken against impeachment, while party leader Han Dong-hoon has voiced support for it. However, Han has faced criticism within the party, with some calling him a traitor.

Party representative Cho Kyung-tae told reporters today that members are leaning towards participating in the vote even as they remain divided on how to vote.

Just a reminder, the vote needs eight PPP members to support impeachment in order to pass.

It's worth noting that the protest in front of the National Assembly calling for Yoon's impeachment is not the only one happening in Seoul.

Another large-scale rally is taking place across town in Gwanghwamun, Seoul's main square and traditional focal point. Those protesters are supporting Yoon. They are calling for the impeachment vote to be shot down, and for opposition leader Lee Jae Myung to be arrested.

The protesters can be seen holding signs saying: "Against impeachment... arrest Lee Jae-myung".

Lee, the head of the opposition Democratic Party, has been pushing for Yoon's impeachment. But he himself is embroiled in multiple legal challenges, after he was indicted on criminal charges.

The pro-Yoon supporters are also waving American flags as they are pro-US. They see themselves in contrast to the opposition who they say is more sympathetic to North Korea.

Image source, Getty Images

Image source, Getty Images

Jake Kwon
Reporting from Seoul

Image source, BBC/Jake Kwon

Kim Sang-wook of the ruling People Power Party (PPP) is currently standing outside parliament holding a huge sign, in a bid to convince other members of the PPP to vote in favour of impeachment.

The sign says: “The outfit I am wearing is the same one I wore on the night of voting down the martial law. I call upon my fellow lawmakers to vote yes on impeachment, remembering how desperately we hoped to lift the martial law. Conservatives will vanish if you stay this course. Yoon Suk Yeol is the traitor of conservatives.”

Currently, at least seven ruling party lawmakers - including Kim - have said they will vote to impeach Yoon. At least eight PPP lawmakers need to vote in favour of impeachment for it to pass.

Support for Yoon from his own party seems to be slipping awaypublished at 04:55 Greenwich Mean Time

04:55 GMT

Jean Mackenzie
Seoul correspondent

Last week more than a hundred thousand protesters turned out calling for President Yoon's impeachment. Today even more people are expected.

It’s been 11 days since President Yoon Suk Yeol stunned this country by trying to impose martial law. He is refusing to resign, meaning it’s now up to politicians whether to force him from office.

For this to happen some members of Mr Yoon’s own party need to vote with the opposition. Last week they shielded him.

But as the President has dug in and people’s calls to remove him have got louder, the support from his party seems to be slipping away.

Image source, BBC/Leehyun Choi

Hundreds of protesters have started gathering in front of the National Assembly, where the impeachment vote is due to take place later this afternoon.

The atmosphere is peaceful, with people giving out newspapers and free hot packs to attendees - sorely needed in Seoul, where temperatures are expected to reach a low of -4C (24.8F).

Some have even dressed up - our reporters on the ground spotted these two women dressed in Rudolf costumes, holding signs that say: "[It will be] a merry Christmas only if Yoon Seok Yul disappears".

Image source, BBC/Leehyun Choi

Thanks for joining us as we bring you live updates from Seoul, where South Korean members of parliament will soon vote on whether they should impeach president Yoon Suk Yeol for his botched attempt to impose martial law.

The country was plunged into some of its worst political turmoil in years following the president's martial law declaration last week. It was quickly withdrawn hours later.

Hundreds of protesters calling for Yoon's impeachment have already gathered in front of the National Assembly, where the vote is set to take place in a matter of hours. More are expected to join.

Calls for his removal from office have been growing steadily. Yoon survived a first impeachment vote last Saturday, when the motion fell five votes short of the 200 needed to pass. This happened after members of Yoon's party boycotted that bill.

Opposition lawmakers, however, have since vowed to hold an impeachment vote every Saturday until Yoon is removed from office. Multiple members of Yoon's People Power Party (PPP) have now indicated that they will vote in favour of the motion today.

Stay with us as we bring you more.