President Park Geun-hye’s liberal foes on Tuesday played down her apology as being insufficient, saying the president clearly lacked understanding of the gravity of her mistake -- letting her inner circle meddle in state affairs, not just in speech writing.

The main opposition Minjoo Party of Korea and People’s Party said that the president’s two-minute mea culpa stopped short of appeasing public outrage over the allegation that Cheong Wa Dae had leaked confidential presidential speeches to Park’s associate Choi Soon-sil, who has never served in public office.

President Park admitted to sharing her presidential speech scripts with Choi, who the president described as “someone who had helped” during Park’s presidential bid in 2012. She described her consultations with Choi as an act done “out of pure heart to be meticulous” in preparing her speeches.

“There are so many things to be proved and such a short apology is insufficient,” said Minjoo spokesperson Rep. Lee Jae-jung. “It is nothing but the same tactics used by the president to avoid communicating with the public about serious cases.”

While the ruling Saenuri Party offered “deep regret” over the scandal following the president’s apology, some moderate Saenuri members echoed the criticism that Park’s explanation was not enough to prove her innocence.

“I believe that she has offered zero explanation about wrongdoings,” said former Saenuri floor leader Rep. Yoo Seung-min, who had clashed with the president over her welfare policies. “I don’t think the president’s apology is enough to wrap up the scandal. More investigation is needed.”

The political parties demanded prompt investigation into the allegation -- raised by cable TV channel JTBC on Monday -- that Cheong Wa Dae had leaked confidential presidential speeches to Choi, who was also allegedly involved in abusing her power to fund dubious government entities by raising money from conglomerates

Opposition parties’ presidential hopefuls, Moon Jae-in of the Minjoo Party and Ahn Cheol-soo of the People’s Party, adopted a more assertive tone. While Moon denounced the scandal for disrupting the national system, Ahn demanded the president herself face investigation and her Cabinet members resign en mass.

The pressure on the president is expected to derail Park’s efforts to amend the current Constitution that she described as currently “unfit” for South Korea. The revision requires approval by two-thirds of the 300-member National Assembly and majority support in a referendum.

“If the allegations are true, President Park should come forward and explain herself,” said Saenuri floor leader Rep. Chung Jin-suk. “We need to find out how Choi Soon-sil has been abusing her power to misguide this country.”

Saenuri also appeared in disarray over the proposed Constitutional amendment. Though the party began working-level discussions over Constitutional amendment Tuesday, its leadership struggled to bring focus to revision of the basic law.

Some Saenuri lawmakers, most of whom belong to the group outside the faction close to President Park, urged the government to name special prosecutors to investigate Choi, whose whereabouts are still unknown since she allegedly moved to Germany.

But some members from the pro-Park faction, such as Saenuri leader Rep. Lee Jun-hyun, appeared to defend the president by saying, “I have also relied on my friends’ help when writing speeches.” Lee served as Park’s senior presidential secretary between 2012 and 2013.

While ratcheting up their attacks against the president over the scandal, the opposition parties vowed to block the president’s attempt to amend the Constitution and denounced the move as an attempt to divert the public’s attention.

“It is an attempt to cover up the snowballing scandal,” said Minjoo leader Rep. Choo Mi-ae during the party’s emergency meeting Tuesday “I don’t think there is anyone in this country who wants to trust such a president with revising the basic law.”

By Yeo Jun-suk (jasonyeo@heraldcorp.com)