NORTH KOREA has warned that the joint military exercises scheduled by the United States and South Korea on Sunday will be considered a provocation that will bring the Korean peninsula to “the brink of war”.

North Korea’s state news agency KCNA condemned the South’s president Lee Myung-bak for having pursued a policy of what it saw as needless aggression that could spark an all-out conflict on the Korean peninsula.

Pyongyang also accused the US and South Korean “puppet forces” of trying to “orchestrate another farce and charade such as the Cheonan [submarine] case” and by staging what it believed were sham meetings of Seoul’s national defence cancel.

South Korea says it heard two new explosions just off Yeonpyeong Island, the site of Tuesday’s artillery shell attack that killed four, and that it is “checking the origin” of those sounds. They were heard between 3am and 6am Irish time, the Straits Times reports.

The new attacks – reported to be another round of artillery fire – sent many of the island’s islands scrambling to air raid shelters, but Seoul believes the attack to have been part of a more routine drill. All of the shells, local media added, landed on the North’s side of the nations’ disputed Yellow Sea border.

China has appealed for calm in the affair, but has done so on far lesser terms than it had done after the Cheonan submarine sinking in March. South Korea blames the North for that affair, though the North had continually denied any involvement.

Barack Obama is likely to call Hu Jintao, the Chinese president, in the coming days to discuss the Korean situation, the Guardian believes.