US Under-secretary of State Nicholas Burns was speaking here after meeting Russian Deputy Foreign Minister Alexander Alexeyev, Moscow's top delegate to six-nation talks aimed at getting Pyongyang to abandon its nuclear program.
South Korea, Japan, Russia, China and the United States have been negotiating with North Korea in the on-off six-party format for more than three years.
"I think the five parties are very strongly together on what needs to be done, and that is the complete denuclearization of the Korean peninsula, the fulfilment of the September 2005 agreement that North Korea has signed up to," Burns told reporters.
"There is strength in the international community that the message to North Korea should be: 'You need to stop your illegal activities'."
Burns said there was agreement that North Korea needs to return to a deal reached during the six-party talks in September 2005.
According to that agreement, North Korea committed to giving up its nuclear weapons in return for security guarantees, normalisation of relations, energy and other aid.
Burns, accompanied by Under-secretary of State for International Security Affairs Robert Joseph, had spoken with Chinese officials on Wednesday and consulted with Tokyo and Seoul on the North Korea issue earlier this week before arriving to Beijing.
Burns said the next round of six-party talks would be on the agenda when US President George W. Bush meets his counterparts, China's Hu Jintao and Russia's Vladimir Putin next week.
That will be during the annual summit of the 21-member Asia Pacific
Economic Co-operation forum in the Vietnamese capital Hanoi.
"We want the (six-party) talks to be very well prepared, so obviously we have the APEC meeting in Hanoi next week when all of our leaders will be there and will discuss these issues," Burns said.
The six-party talks have been stalled since late last year due to a North Korean boycott.
However, North Korea agreed last month to return to the talks, with the main speculation now centring on when they will take place.
"We hope we'll have the talks in 2006, so that leaves us just two months. But there is no agreement on when. And frankly that is not the most important issue," Burns said.
"The most important issue is that there is real unity among the parties. And from the conversations we've had this week we are going to move ahead with strength and conviction and the goal is the denuclearization of the Korean peninsula."
Joseph said after the talks with Russia that the two sides were "entirely agreed on full and effective implementation of the UN Security Council resolution 1718" which imposes sanctions on North Korea.
Meanwhile, Alexeyev emerged from the meeting saying both sides "satisfied each other" on the issue of resolution 1718.
"We did not discuss (the timing of the six-party talks)," Alexeyev told reporters. "But we both understand that the next round will take place."
Burns met Wednesday with Chinese Foreign Minister Li Zhaoxing and other senior Chinese diplomats. He was scheduled to hold further talks with Chinese officials Thursday.

Copyright AFP (Agence France-Presse), 2006