South Korea’s liberal opposition parties voiced concerns Friday over domestic and international moves to toughen sanctions on North Korea, which they argue have proved ineffective in taming the reclusive communist state.

The largest opposition Democratic United Party, which advocates a policy of engagement and reconciliation with North Korea, urged the South government to take care not to further escalate tensions, while condemning the communist state for the rocket launch.

On Friday morning, Pyongyang unsuccessfully fired a long-range rocket, defying international pressure and United Nations resolutions. The U.S. said it may suspend plans to send food to the impoverished North, which it had promised Pyongyang in return for its rollback of nuclear programs.

“The (South Korean) government must do its best to prevent the current tension from escalating to a degree that threatens the peace on the Korean Peninsula,” its spokesperson Park Yong-jin said.

“All parties to the six-nation talks need to pool their wisdom to find a peaceful way out from the current situation,” he added, referring to the multinational dialogue involving two Koreas, the U.S., China, Japan and Russia to denuclearize the North.

The DUP suffered an unexpected loss in Wednesday’s general election, securing 127 of the 300 seats in the new National Assembly.

“We must not act in a huff now,” said Rep. Park Jie-won, the party’s former floor leader and currently a member of its top decision-making Supreme Council.

“From the way things look, inter-Korean relations will be frosty for some time. But after all, we need to engage in dialogue and provide humanitarian aid to induce the North to open up,” he said.

The far-left minority Unified Progressive Party, which won 13 seats in the parliament in Wednesday’s general election, said U.S.-led U.N. sanctions would not help ease the tension.

“An all-stick, no-carrot approach will not help ease the tension on the Korean Peninsula,” Woo Wi-young, the party’s spokesperson said. “The matter should be solved through dialogue and negotiations.”

The conservative camp used a distinctively different tone in their response to Pyongyang’s failed rocket launch.

The governing Saenuri Party stressed a coordinated response between South Korea and the international community, while condemning the North’s provocative action.

“The government should handle this issue in the U.N. Security Council and take any steps in close coordination with the international community,” its chief Park Geun-hye said.

She also noted the need for countermeasures to safeguard South Koreans from North Korea’s missile threats.

The far-right Liberty Forward Party called on the government to sternly deal with the North Korean provocation.

“We must let them realize that a provocative act has its consequences.”

By Lee Sun-young (milaya@heraldcorp.com)