Tension rose Wednesday between the main opposition Democratic Party of Korea and three other parties over when and how to revise the nation’s Constitution.

While the three parties claimed that the issue of altering the basic law may no longer be delayed, the Democratic Party -- especially its presidential front-runner Moon Jae-in -- saw it as an arbitrary action, short of public consensus.

The floor leaders of the Liberty Korea Party, People’s Party and Bareun Party agreed Wednesday morning that a referendum should be held along with the upcoming presidential election on May 9.

“The Bareun Party and the Liberty Korea Party decided to join in the Constitution revision led by the People’s Party and some members of the Democratic Party,” said Rep. Kim Dong Dong-cheol of the People’s Party, chairman of the parliamentary committee on constitutional reform.

The Liberty Korea Party had previously attempted to push for the revision before the presidential election but due to the pressing timeline, turned to the idea of holding a referendum simultaneously with the election.

The key point of the law amendment, according to Kim, will be to decentralize the current state powers, which are largely monopolized by the president.

With the ouster of former President Park Geun-hye upon her impeachment Friday, the next presidential election is to be held on May 9.

The three consenting parties plan to jointly motion a constitutional revision bill with the signatures of 150 or more of the 299 parliamentary seats by next week.

Their plan, however, faces challenges as two of the leading opposition presidential hopefuls set out to deter a hurried law revision.

“The discussion (to hold a referendum on constitutional revision on election day) is a denial of national sovereignty,” said former Democratic Party chief Moon in a press conference.

“How can politicians arbitrarily decide to adopt a Cabinet government or a semi-presidential system (without the people’s consent)?”

Citing recent polls in which a majority of the respondents turned out to be hesitant over a revision, Moon argued that the detailed process of altering the basic law should be handed over to the incoming administration.

The Democratic Party and its candidate Moon have been focusing on maintaining the progressive-leaning political momentum following the ouster of former President Park.

Backing Moon’s opposition, the Democratic Party’s Floor Leader Rep. Woo Sang-ho accused the three parties’ plan of being “unrealistic,” saying a crucial issue such as constitutional revision would require the participation of the majority party. The 121-seat main opposition party is currently the single-largest cluster in the 300-seat National Assembly.

Rep. Ahn Cheol-soo, former chairman of the People’s Party and once rival to Moon in the 2012 presidential election, also countered the referendum plan, standing at odds with the leadership of his own party.

“The Liberty Korea Party should be making sincere apologies for the dismissal of the president, instead of calling for constitutional reform,” said Ahn, adding that an amendment of the basic law should at all times be based on public consensus.

Both Moon and Ahn consider the local elections in June next year as a more plausible time to ask the nation to vote on the constitutional revision bill.

But regardless of the conflict over the schedule, some observers point out that the trilateral agreement on the May 9 referendum may hold no effect after all. The greatest obstacle, considering the backlash from the Democratic Party and the People’s Party, is the quorum of 200 that is necessary to pass the revision bill at the parliamentary floor.

The three parties, which together hold 171 seats, hope to induce the participation of the Democratic Party’s minority groups, as well as some independent lawmakers, so as to meet the quorum.

By Bae Hyun-jung (tellme@heraldcorp.com)