The United States said on Monday it remained confident China would uphold its promise to impose UN sanctions on North Korea and said it had confirmed Pyongyang had set off a nuclear blast.
Secretary of State Condoleezza Rice, who travels to the region this week trying to stiffen the resolve behind sanctions, dismissed skepticism among some in Washington about China's commitment to tough action against its communist neighbour.
"I am not concerned that the Chinese are going to turn their backs on their obligations," she said. "I don't think they would have voted for a resolution that they did not intend to carry through on."
US Under Secretary of State Nicholas Burns said China was already taking action to check goods crossing into North Korea. "The Chinese now are beginning to stop trucks at the 800-mile (1,400 km) border and inspect all of them," he said on CNN.
China has made clear it is worried that tough action could provoke a collapse of the impoverished and highly militarised state, and its UN ambassador again clarified the limits of its action on Monday.
"Inspections yes, but inspections are different from interception and interdiction." Ambassador Wang Guangya told reporters, an apparent reference to stopping cargo at sea, which is one of the UN sanctions agreed to on Saturday.
Wang said the resolution did not make it mandatory for all nations to inspect cargo going to and from North Korea. He said states could carry out such an operation as necessary "in accordance with their national legal authorities."
BLAST CONFIRMED
The US government confirmed that the Oct. 9 explosion, which prompted world-wide condemnation and the harsh sanctions regime, was a nuclear explosion as Pyongyang claimed.
"Analysis of air samples collected on October 11, 2006, detected radioactive debris which confirms that North Korea conducted an underground nuclear explosion," the director of national intelligence said in a statement.
Rice leaves for Tokyo, Seoul and Beijing on Tuesday to try to cement the unified UN approach and edge North Korea back toward six-party talks aimed at stopping its program to build a nuclear weapon.
"My goal on this trip is, certainly, to reiterate that we're prepared to return to the talks. But North Korea also needs to understand ... that they will pay a price here (because of the test)," she said.
US officials also said North Korea must do more than return to the talks to have the sanctions lifted. "A return to six-party talks kind of doesn't do it," Ambassador to Japan Thomas Schieffer said.
Pyongyang had to commit to implementing an agreement from Sept. 19, 2005, in which it promised in principle to scrap its nuclear arms programs in return for aid, security assurances and promises of better diplomatic ties.
There were signs the new web of sanctions was starting to be put in place. Australia said it was prohibiting all North Korean ships from entering Australian ports and Japan announced it was extending already harsh restrictions.
'DIFFERENT DREAMS'
But Professor Nam Sung-wook of Korea University, an expert on North Korea, said the practical effect was questionable. "They (countries supporting sanctions) are in bed together but they're all dreaming different dreams," he said.
Most of Pyongyang's trade crosses through China, which has perhaps the most leverage on the reclusive state but fears a flood of refugees if the Pyongyang government collapses.
Xu Guangyu of the government-sponsored China Arms Control and Disarmament Association institute in Beijing, said inspecting cargo for weapons-related material was "more a symbolic step than a real sanction measure."
"China just doesn't engage in that sort of trade with North Korea, so there's not much practical that needs to be done. It lets North Korea know our feelings." Weapons comprise a tiny fraction of the two countries' $1.5 billion trade.
US analysts said Chinese and South Korean participation in the sanctions was vital. "There is no way North Korea is going to negotiate seriously, if ever, as long as they know China and South Korea will bail them out," said Winston Lord, a former US ambassador to China.
The UN sanctions bar trade with North Korea in dangerous weapons, impose bans on heavy conventional weapons and luxury goods and ask nations to freeze funds connected with North Korea's non-conventional arms programs.
In Paris the next secretary general of the United Nations, Ban Ki-moon, told the Le Monde newspaper there was still room for dialogue with North Korea and he was prepared to travel to Pyongyang for talks.