SEOUL -- The Democratic People's Republic of Korea (DPRK) threatened Monday to cut off a military communication channel with Republic of Korea (ROK) and to stop talking with its southern rival, an apparent reversal of its recent push for dialogue.

Seoul blames the DPRK for two deadly attacks against it last year that killed 50 people and dismissed Monday's warnings as part of Pyongyang's pattern of making threats and then easing tensions in order to wrest concessions from Seoul and other nations.

The DPRK has appealed for food aid this year, and leader Kim Jong-il in late April reportedly proposed summit talks with ROK President Lee Myung-bak.

On Monday, however, the DPRK said it will no longer deal with ROK, accusing Seoul of worsening animosity by holding firing drills near the border and aiming propaganda at the North.

"The moves of the Lee Myung-bak group of traitors to escalate confrontation with (the DPRK) have reached an extreme phase," Pyongyang's powerful National Defense Commission said in a statement carried by the official Korean Central News Agency.

The statement renewed a warning that Pyongyang will take unspecified "physical actions" against Seoul over its propaganda campaign, which includes radio broadcasts.

The DPRK also said it planned to cut off communications along the countries' eastern border and shut down a liaison office in a now-stalled joint tourism facility in the DPRK. The statement, however, doesn't mention other military and nonmilitary hotlines across the border.

Seoul quickly downplayed Pyongyang's warning. "The DPRK has often said it wants talks while applying pressure on us at the same time. We see (the latest threat) as part of such an offensive," Unification Ministry spokeswoman Lee Jong-joo said.

The two Koreas are still technically at war because their 1950-53 conflict ended with an armistice, not a peace treaty.