That's according to Chinese diplomatic sources quoted by the Kyodo News Agency, who said early Monday that there was a possibility China might use its veto if the United Nations went ahead with a vote Monday on the Japanese-proposed resolution.
Several hours after that report became public, Japan delayed the vote.
"I don't think we have to push too much for a vote" on Monday said Japanese Prime Minister Junichiro Koizumi, according to the Kyodo News agency.
The United States, Britain and France have expressed support for Japan's proposal to impose sanctions on North Korea.
China and Russia, the North's traditional allies, have voiced opposition to the resolution. Both are permanent members of the Security Council, with power to veto U.N. actions.
"The threats from North Korea are ones that the world powers must take seriously, but are designed to prevent action to sanction Pyongyang at the U.N. Security Council," says CBS News Foreign Affairs Analyst Pamela Falk. "And without a clear reading on whether China would abstain or veto, the sponsors of the Resolution will have to make tough decisions before bringing it to a vote early this week."
"China has not vetoed a resolution in the past six years and that is what the Administration is banking on when it says it has the votes," adds Falk, "but the stakes are high and the language of the U.N. resolution circulated by Japan, France, the U.S. and Britain might have to be changed to gain unanimous support."
South Korea has already said it will be suspending planned shipments to North Korea of food and fertilizer.
Japan, for its part, is considering whether a preemptive strike on North Korean missile bases would be an acceptable form of self-defense under the pacifist Japanese constitution.
"There is the view that attacking the launch base of the guided missiles is within the constitutional right of self-defense. We need to deepen discussion," said Shinzo Abe, Japan's Chief Cabinet Secretary.
Japan's constitution currently bars the use of military force in settling international disputes and prohibits Japan from maintaining a military for warfare.
A Chinese vice premier arrived in North Korea on Monday as Beijing sought to push its communist ally back into nuclear disarmament talks amid outrage over North Korean missile tests.
Chinese Vice Premier Hui Liangyu arrived in Pyongyang, North Korea, Monday for a six-day visit to celebrate the 45th anniversary of a friendship treaty between the North and China.
That's according to China's Xinhua government-run news agency, which did not say whether the nuclear crisis will be on the agenda for the two leaders.
Hui's delegation to North Korea includes Vice Foreign Minister Wu Dawei, China's chief nuclear negotiator.
Saturday, a new top-of-the-line U.S. guided missile destroyer with missile-tracking radar was deployed to Japan.
A top U.S. envoy said Monday that the international community needs to say in one voice that the communist nation's missile tests last week were unacceptable.
U.S. Assistant Secretary of State Christopher Hill, commenting in Tokyo after a meeting with Japanese Foreign Minister Taro Aso, told reporters the U.S. is demanding that North Korea return to six-nation nuclear disarmament talks.
The talks have been deadlocked since November because of Pyongyang's boycott over a crackdown by Washington on the regime's alleged money-laundering and other financial crimes.
"I must say the issue of China's influence on DPRK is one that concerns us... China said to the DPRK, 'Don't fire those missiles,' but the DPRK fired them. So I think everybody, especially the Chinese, are a little bit worried about it," said Hill, referring to the North by the initials of its official name.
North Korea's ambassador to Australia warned Sunday that international attempts to halt his nation's missile tests could lead to war.
In a letter to The Sunday Herald Sun newspaper in the southern city of Melbourne, Ambassador Chon Jae Hong defended last week's missile launches as "routine military exercises" aimed at increasing the nation's "capacity for self-defense."
He said North Korean's missile program and tests were key to keeping the balance of force in northeast Asia.
"It is a lesson taught by history and a stark reality of international relations, proven by the Iraqi crisis, that the upsetting of the balance of force is bound to create instability and spark even a war," Chon said.
North Korea "will have no option but to take stronger physical actions of other forms, should any country dare take issue with the exercises and put pressure upon it," he added.