Main opposition party leader Lee Jun-seok continued to bicker with his own party members supporting former prosecutor general and presidential hopeful Yoon Seok-youl despite concerns that internal fighting will not help the party win next year’s election.

The People Power Party plans to hold a debate between the party’s preliminary presidential candidates on Aug. 18, which members of Yoon’s camp have expressed discontent with, saying everyone will attack Yoon, the leading candidate.

Shin Ji-ho, a deputy chief of Yoon’s camp, said in a radio interview Wednesday evening that no man of power can arbitrarily exercise his authority in a republic, as he criticized a planned debate session arranged by the party’s primary preparation committee.

When the show host mentioned that candidates had different views about the party leader’s decision, Shin said, “even if it’s the party leader’s decision, even if it’s the president, anything not based on the Constitution or the law can be subject to impeachment.”

The debate has no institutional grounds nor precedents, Shin said.

Lee wrote on Facebook Thursday morning that now that they were mentioning “impeachment,” it is clear what they are after.

Shin later said his “impeachment” comment was not targeted at Lee, but it was too late.

Rep. Kim Jae-won, a member of the PPP’s supreme council, told Shin to leave the camp, and called for discipline by the party’s ethics committee.

Rep. Hong Joon-pyo, another presidential contender, wrote on Facebook, “a person (Yoon) who led the destruction of right-wing conservatives turned because he was thrown out after being used, and now acts like some occupation force shaking the party leader with some childish politicians -- it really is a sight.”

Members of Yoon’s camp and other PPP presidential contenders such as former Jeju Gov. Won Hee-ryong believe Lee is behind the primary preparation committee that plans to hold many debates throughout the primary.

Yoon did not attend events organized by the party for preliminary candidates, and people in his camp have persuaded others to boycott them too.

Lee shared a news article about Won saying he was asked by a member of Yoon’s camp to not attend an event where preliminary candidates visited the poor to deliver food.

Lee wrote on Facebook that he will see whether there are appropriate measures for inappropriate remarks by people in key positions within Yoon’s camp.

Some of them suspect that by pushing ahead with the debates, where Yoon, a novice in politics, doesn’t appear likely to fare well, Lee is seeking to increase the chances of former Assembly member Yoo Seung-min or someone else.

Lee did say in a YouTube broadcast in March this year that he would leave the Earth if Yoon gets elected.

Asked what he was going to do if People’s Party leader Ahn Cheol-soo becomes Seoul mayor and Yoon becomes president, Lee said he would leave the Earth, bursting into laughter.

Lee also said during the same show that he would make Yoo Seung-min president. Lee was previously a member of the supreme council of the Bareun Mirae Party led by Yoo.

Yoon’s camp appears to have been wary of this, and has been quite upfront, if not insinuating, about it.

Yoon, who had been mulling for months whether to join the PPP, joined the party while Lee was away in Gwangju, and made Lee wait for 15 minutes in the corridor during the party’s welcoming ceremony for him.

Rep. Chung Jin-seok, five-term lawmaker and key member of Yoon’s camp, openly criticized Lee for putting “dolphins, mackerels and anchovies,” or candidates of different weight, in the same pool when they all have different conditions for growth.

Lee had responded by saying he was trying to give mackerels and anchovies a fair chance to let their ideas be known to the public, and the dolphin’s team is not happy with that.

Yoon himself on Wednesday denied conflict with Lee, saying he recently met and spoke on the phone with the 36-year-old PPP leader, and that he doesn’t stop seasoned politicians in his camp from saying what they want.

The PPP saw its membership increase by some 110,000 in just two months after its national convention on June 11 where Lee was elected its leader.

According to the party, 111,689 people joined the party after Lee took helm, about 30 percent of whom were in their 20s and 30s.

Yoon’s joining of the PPP on July 30 has also had an impact on the increase of membership.

Some 29,399 people joined the PPP between July 30 and Aug. 10, nearly half of whom are in their 50s and 60s.