"Is there anything to do if the United States does not change its position?" said Song Il Hyuck, a member of the North Korean delegation at a security conference in Tokyo.

Song said North Korea had never been opposed to the six-way talks on halting its nuclear programme. He said it was ready to return to talks if the US lifts financial sanctions imposed on North Korean companies for alleged illegal activities.

North Korean officials have no plans to hold bilateral meetings with their US counterparts, but would oblige if there was a request, Song said.

US officials have said that Christopher Hill, the assistant-secretary of state, has no plans for a one-on-one meeting with North Korean delegation on his arrival in Japan on Monday.

Song's comments came amid a flurry of diplomatic activity on the sidelines of the private security conference attended by delegates from the six-party nuclear talks.

The meeting had raised hopes that they would be able to find common ground on which to relaunch the stalled nuclear talks.

On Sunday, Tadamichi Yamamoto, the Japanese ambassador in charge of the North Korean nuclear issue, met with another North Korean delegation member, Jong Thae Yang, with no apparent progress, news reports said.

Kim Kye Gwan, North Korea's top negotiator, who arrived in Tokya on Friday, has already met his South Korean and Japanese counterparts at separate meetings.

Although no comment has been made publically, observers said they did not appear to have made any progress towards resuming the six-nation talks.