The U.S. says time is running out in fulfilling a six-party nuclear deal to dismantle North Korea's nuclear programs.

''Time is an important factor because if we're going to try to get this thing done in '08, we really do need to pick up the pace," Hill said. "We cannot get on to the Phase Three elements until we complete Phase Two. And obviously it's going to be difficult because we still don't have a declaration."

The comments came upon Hill's arrival in Seoul Tuesday evening, following a sudden meeting with his North Korean counterpart Kim Kye-gwan in Beijing.

Hill added there is no talk of a phased declaration but that the North was interested in figuring out a way to untangle the current deadlock.

Tuesday's Beijing discussion between Washington and Pyongyang envoys was the first of its kind after North Korea missed its December 2007 deadline to disable and declare its nuclear programs.

Washington and Pyongyang are at odds over what a ''complete and correct'' declaration means, stuck particularly over the regime's alleged uranium enrichment program.

The other part of the six-party nuclear deal is to send economic and energy aid to the North for its disablement, but Pyongyang is upset over the delay in receiving the promised heavy fuel oil.

Another working group meeting between South Korea, the U.S. and China will be held Thursday in Beijing on sending non-heavy fuel aid like construction materials.

Washington's nuclear envoy will meet his South Korean counterpart and members of the incoming administration Wednesday for talks on the nuclear issue and to prepare for U.S. Secretary of State Condoleezza Rice's visit.

But it is the sudden Washington-Pyongyang meeting in Beijing that has raised questions of a possible breakthrough in the deadlocked six-party process.

Arirang News