Turmoil might be ahead for the ruling People Power Party, with its ethics panel set to rule on allegations facing Chairman Lee Jun-seok on Thursday.

The ruling party’s internal ethics panel will decide whether to penalize Lee for “failing to maintain dignity” and “coercing to destroy evidence” in relation to a sexual bribery case, at 7 p.m. Thursday.

Police have been investigating allegations that Lee received sexual favors as well as bribes worth 11.5 million won ($8,800) from a businessman in 2013. Lee was then a member of the emergency steering committee for the Grand National Party, the predecessor of the People Power Party.

It is widely believed that the panel will move to penalize Lee, but the severity of the penalty remains uncertain.

The panel decided earlier to begin the process of reprimanding a key aide to Lee over allegations that he met with the unidentified informant earlier this year and attempted to silence him by offering a promise of investment.

The move has fueled speculations that the panel would also hand down a penalty for Lee at Thursday’s meeting.

One of four penalties -- a warning, party membership suspension, request to relinquish party membership or forced membership termination -- is likely, and anything other than a warning is expected to cause intense turmoil among party members.

The ruling is expected to spur competition over who will take control of the party’s steering wheel instead of Lee.

Cracks within the party, which have been forming since the end of the local elections last month, are also likely to widen. Calls have grown for Lee to step down and let a new leader take his place to create synergy with the Yoon Suk-yeol administration.

Lee has faced increasing opposition from his own party, especially those claiming to be close aides of Yoon, after he announced to launch a special committee to overhaul nomination guidelines for the next general elections in 2024.

“Just look at the attack made on the special committee and my visit to Ukraine,” Lee said in a recent radio interview. “Isn’t it clear that so-called ‘close aides of Yoon’ are coming after me?”

Lee accused the ethics panel of being manipulated by those in the pro-Yoon circle and that they are aiming to unseat him in fear of losing power and authority as a result of his proposed reform measures.

The chairman has denied all allegations made against him thus far.

Rep. Kweon Seong-dong, floor leader of the People Power Party who is one of Yoon’s closest aides, rejected claims of the president’s involvement and said that he has never discussed the allegations and possible penalization in conversations with Yoon.

“It is simply not right to have the president involved in a problem pertaining to the party,” Kweon said in an interview with JoongAng Ilbo released Wednesday. “It is weird to ask the president on party matters, which should be discussed and ruled solely within the party.”

But the ethics panel could also delay the ruling once again, as it faces criticism of having moved too hastily when the police investigation has not even been finalized. The panel had already ruled on June 23 to push back its verdict by two weeks.

The ongoing dispute has taken a toll on the public’s opinion of the People Power Party. A Realmeter survey of 2,514 adults conducted from June 27 to July 1 found that the party’s support rating slid 1.3 percentage points from a week earlier to 43.5 percent.