The divide between political parties over when to hold a public referendum on constitutional revision has delayed the opening of a plenary session, raising concerns that pending bills will be held off until next year.

The one-month parliamentary session for December, which was to end Saturday, was automatically extended to Jan. 9 after a plenary session scheduled Friday was canceled.

The ruling Democratic Party of Korea seeks agreement on a bill to amend the Constitution by February and to hold a referendum on the revision along with local elections slated for June 13.

The main opposition Liberty Korea Party, however, says the ruling party’s move is hasty, rejecting the proposal to set a deadline. It also called for extending the operation of a special parliamentary committee on constitutional reform by six months. The committee’s yearlong work is scheduled to end by this year.

On Tuesday, the Democratic Party criticized the Liberty Korea Party for taking pending bills “hostage” and urged the conservative party to cooperate.

“The Liberty Korea Party not only unilaterally thwarted the regular plenary session on Friday, but is also taking an unyielding position despite our cooperation,” Floor Leader Rep. Woo Won-shik said at a party meeting. “The opposition party should quickly return to the floor and cooperate to pass bills on livelihoods.”

First-term lawmakers from the ruling party also held a press briefing early in the day to stress the importance of constitutional revision.

“All parties agreed to put constitutional reform to a referendum in June local elections, during the presidential election period. We urge all politicians across the aisle to keep their promise,” said the group of 57 lawmakers.

The conservative opposition, however, continued to denounce the ruling party and the government, calling them “high-handed.”

“The government is attempting to push through the constitutional amendment without the main opposition’s consent,” Floor Leader Rep. Kim Sung-tae said at a press conference in front of Cheong Wa Dae.

“Constitutional reform should proceed at the National Assembly and garner political consent. We should not give up on the revision just because it is difficult to reach an agreement,” first-term lawmakers and members of a special committee from the main opposition party said in a statement. “We promise to make efforts to settle constitutional reform before the end of next year.”

Due to the political standoff, lawmakers have not yet passed a motion on the appointment of the chairman of the Board of Audit and Inspection and the Supreme Court justice.

Pending bills on welfare and safety are expected to be pushed to next year if lawmakers fail to open a plenary session before the end of month.

The special committee on constitutional reform was established in January amid demands for changes to the Constitution, which was last revised in 1987. A wide range of topics -- from basic rights and decentralization to election and governing systems -- have been discussed at the parliament, but the special parliamentary committee of both ruling and opposition party lawmakers has not yet produced an amendment bill that they agree upon.

The ruling party advocates a four-year, two-term presidency, while opposition parties appear to prefer a semi-presidential system where a president takes charge of foreign affairs while a prime minister or the chairman of the biggest party is put in charge of domestic issues.

By Jo He-rim (herim@heraldcorp.com)