China called for emergency talks on resolving a crisis on the Korean peninsula on Sunday, and Seoul and Tokyo said they would study the proposal, as the US and South Korean militaries started a massive drill. Beijing's move to bring the two Koreas to the negotiating table comes after global pressure on China to take a more responsible role in the stand-off and try to rein in ally Pyongyang.
China made clear the talks would not amount to a resumption of six-party disarmament discussions that North Korea walked out of two years ago and declared dead. South Korea said it would carefully consider China's suggestion.
Both Beijing and Pyongyang have been pressing regional powers to return to talks, in some form or other, for the past few months in a move analysts say is designed to extract concessions.
China, which agreed with South Korea that the situation was "worrisome," suggested the emergency talks for December among North and South Korea, host China, the United States, Japan and Russia. It did not say whether Pyongyang had agreed to join.
Japan was non-committal. "We want to respond cautiously while co-operating closely with South Korea and the United States," Kyodo news agency quoted Deputy Chief Cabinet Secretary Tetsuro Fukuyama as saying.
Beijing has longstanding bonds with Pyongyang, and has sought to shield its small, poor neighbour from a backlash that China fears could draw an even more ferocious reaction from North Korea and dangerously destabilise the region.
Critics in Washington and other capitals have said China's approach amounts to coddling a dangerous nuclear-armed state.
John McCain, a Republican senator who lost to President Barack Obama in the 2008 White House race, said China should do more to restrain North Korea.
"Unfortunately, China is not behaving as a responsible world power," McCain told CNN's "State of the Union" program on Sunday. He said the call for talks was "a fine first step" but was not enough.
South Korea's marine commander on Saturday vowed "thousand-fold" revenge for the North Korean attack. North Korea said that if there had been civilian deaths, they were "very regrettable," but that South Korea should be blamed for using a human shield.
It also said the United States should be blamed for "orchestrating" the whole sequence of events to justify sending an aircraft carrier to join the maritime manoeuvres.
Yonhap new agency in Seoul said North Korea, whose ailing leader, Kim Jong-il, is preparing to hand over power to his youngest son, had moved surface-to-air and surface-to-surface missiles to frontline areas, days after it shelled Yeonpyeong killing four people. The North's official KCNA news agency warned of retaliatory action if its territory is violated.
South Korea's Defence Ministry told journalists to leave the island on Sunday because the situation was "bad." Many residents evacuated earlier said they did not want to return.
In Seoul, life carried on normally for the city's more than 10 million residents, with downtown shopping districts jammed with people despite the freezing temperatures, and cafes decked with Christmas decorations doing brisk business.
"I am worried, but not that worried that I need to stay at home," said Eunhye Kim, an usher showing people from a packed theatre in the capital. "They don't really want to make war ... there's no gain for either side."
The around-the-clock exercises, in waters well south of the disputed maritime boundary off the west coast, are being held in the face of misgivings by China and threats of all-out war from North Korea.