Fresh diplomatic efforts are under way to end the increasingly bitter row between international allies over what do about North Korea's missile tests.
China's UN envoy warns sanctions could make the situation worse
The senior US envoy on North Korea's nuclear issue is on an unscheduled return visit to Beijing amid China's opposition to the threat of sanctions.
A top Chinese team is in North Korea, expressing concern about the situation.
But there are still splits at the UN on Japan's draft resolution, backed by the US, France and UK, condemning N Korea.
North Korea raised tensions last week when it test-fired seven missiles - including a long-range Taepodong-2, a weapon which is believed to be capable of reaching Alaska.
In response, Japan drafted a resolution branding North Korea a "threat to international peace and security" and invoking Chapter Seven of the UN charter.
Resolutions made under Chapter Seven are legally binding and can authorise sanctions or even military action.
China, which proposed a statement condemning the tests but stopping short of sanctions, says the Japanese proposal is an "over-reaction".
"If approved, it will aggravate contradictions and increase tension," a foreign ministry spokeswoman said.
Seoul has also reacted with alarm over Japan's stance over North Korea.
A South Korean presidential spokesman accused Japan of acting recklessly and obstructing peace, after Tokyo suggested the possibility of pre-emptive strikes against North Korean missile sites.
Amid these tensions, the flurry of diplomatic activity continues.
The American envoy to North Korea, Christopher Hill, is currently holding talks in Beijing, and a high-level North Korean delegation has just arrived in Seoul.
The international community is angry at the North's missile tests
According to our correspondent at the UN, Richard Galpin, China and Russia, which both have the power of veto in the Security Council, believe that using a UN resolution to impose sanctions on North Korea at this stage would be irresponsible and unconstructive.
China's UN ambassador Wang Guangya said such action "could make the situation even worse" and that China was worried it could ultimately pave the way for military action against North Korea.
Instead, he believes the best initial response is a non-binding statement by the Security Council calling on Pyongyang to stop the development of ballistic missiles and halt any testing.
That approach is backed by the Russian envoy to the UN, Vitaly Churkin, who said the statement provided "an excellent basis for a strong signal to Pyongyang" and "the right mode of action".
But the US, UK and France, also permanent members of the Security Council, say it is far too weak, especially as it is not legally binding.
All 15 members of the Security Council have at least agreed to hold off from voting immediately on a resolution calling for sanctions to give time for China to resolve the crisis through diplomatic means.
A Chinese delegation arrived in Pyongyang on Monday to hold talks with North Korean leaders.
US Secretary of State Condoleezza Rice said the Chinese mission "has some promise, and we would like to let that play out".
But after a meeting in Tokyo with the Japanese foreign minister, US nuclear negotiator Christopher Hill expressed doubts about the extent of Beijing's influence over Pyongyang.
"I must say the issue of China's influence on the DPRK [North Korea] is one that concerns us, because China said to the DPRK, 'Don't fire those missiles', and the DPRK fired them," he said.
Mr Hill has been visiting several countries in the region as part of diplomatic moves to decide how to respond to last week's tests.