The Bareun Party spun off from the ruling party earlier this year after factional feuds among President Park Geun-hye's loyalists and dissenters. Park was impeached by parliament in December over a corruption scandal involving her confidante Choi Soon-sil.

Nam said Yoo should "return to the Saenuri Party" if he wishes to join hands with those that played key roles in the scandal, referring to the former name of the Liberty Korea Party. The party changed its name recently.

"Bareun Party colleagues already concluded it cannot join forces with those responsible for the scandal. The party was created with the spirit of seeking a true conservatism and breaking from the old vested groups," Nam said.

Ahead of the presidential election, which may come as early as May, conservative parties face difficulties in securing competent candidates, prompting discussion about the possibility of a united campaign.

Moon Jae-in of the main opposition Democratic Party currently leads local opinion polls, followed by South Chungcheong Gov. An Hee-jung from the same party.

Acting President and Prime Minister Hwang Kyo-ahn is the only conservative figure with a two-digit approval rating, though he remains noncommittal about his presidential ambitions. (Yonhap)