The United States on Sunday pushed China to apply more pressure on North Korea to end its missile tests and return to international nuclear disarmament talks. A top diplomat said the aim is to show that Kim Jong Il's government has "no support in the world."

CountryWatch: China

Undersecretary of State Nicholas Burns also indicated the United States would not grant North Korea the direct talks it is seeking in the wake of its test-firing of seven missiles, including some that possibly could reach the American continent. President Bush has opposed one-on-one talks, too.

"We really don't see the logic of turning this into a test of wills between two countries — the United States and North Korea," Burns said.

The diplomatic goal is to compel North Korea to return to stalled six-nation talks aimed at ridding the reclusive communist-led nation of its nuclear weapons program, Burns said. The U.S. consistently has rejected direct talks with North Korea, preferring the six-party negotiations, deadlocked since November.

CountryWatch: North Korea

Getting support from China, North Korea's main ally and trading partner, is seen as crucial. Burns, joined by members of Congress, urged Beijing to use "its "influence and exert some pressure on the North Korean regime to get it to come back to the six-party talks and end these missile tests."

Burns, appearing on four talk shows as the administration's point man on North Korea, said the U.S. is "engaged now in a very complex series of diplomatic steps from multiple directions" to get the North to return to the talks that involve the Koreas, the United States, China, Russia and Japan.

CountryWatch: Japan

These efforts, he said, are aimed to "convince the North Koreans that they're isolated, that they have no support in the world, and they've got to come back to this six-party framework."

Chris Hill, the top U.S. envoy to the nuclear negotiations, has been in Asia, talking to his diplomatic counterparts; Secretary of State Condoleezza Rice and President Bush have been calling world leaders in the region; at the United Nations, Japan has proposed a Security Council resolution calling for penalties against North Korea.

The U.S., Britain and France support the idea, but the other two veto-empowered members of the council, China and Russia, are opposed.

Burns expressed confidence that a united message could be sent. China and Russia, he said, "understand that, as two members of the six-party framework, they have a responsibility to use their influence with North Korea."

Sen. John McCain, R-Ariz., said that how Beijing handled North Korea would be a "defining issue in our relations with China." He suggested that if China continues to "vacillate" in the United Nations that "there are consequences in our relationship."

"There are many key areas that we are cooperating in that I believe would be affected, including trade, by China's failure to act," McCain said.

Sen. Richard Lugar, chairman of the Senate Foreign Relations Committee, is now relenting from his earlier advocacy of direct negotiations.

"The shots eliminated the efficacy of that," said Lugar, R-Ind.

The Washington-based Institute for Science and International Security estimated in a recent report that North Korea has enough separated plutonium to develop an arsenal of four to 13 nuclear weapons, compared with estimates of one or two nuclear weapons at the start of the Bush administration.

Burns appeared on CNN's "Late Edition," "FOX News Sunday," CBS' "Face the Nation" and NBC's "Meet the Press."