Delegations from the North Korea and the United States failed to narrow their differences during their meeting on Friday, forcing the marathon six-party talks to stretch into the 12th day.

The fourth round of six-party talks on the Korean Peninsula nuclear issue, involving China, the North Korea, the United States, South Korea, Russia and Japan, remained deadlocked and the six parties are still striving for a common document. No end date has been set yet.

US chief negotiator Christopher Hill told reporters Friday evening that the talks reached "little progress" and the US delegation will meet with the North Korea and Chinese counterparts on Saturday in a bid to push forward the process.

Ri Gun, the North Korea's deputy negotiator, and his US counterpart Joseph DeTrani had a one-hour bilateral meeting in the morning. They discussed such issues as the North Korea's peaceful use of nuclear energy and the scope of denuclearization on the Korean Peninsula, according to Song Min-soon, South Korea’s chief negotiator.

But the two sides "failed to narrow their differences," said Song.

Besides North Korea-US bilateral contacts, a series of other bilateral meetings were also held on Friday, between the South Korea and the US, the North and South Korea, China and the US, China and Japan.

As for the proposed common document, Song said, "We want a clear not an ambiguous result of the talks...But given the fact that no concessions have been made (by the six parties) clearly, ambiguity is inevitable."

"I'm not saying that ambiguity is indispensable at the current stage as all the parties concerned need to continue consultations," he added.

Observers noted there are major differences between the North Korea and the United States in several issues, especially whether the North Korea should have the right to use nuclear technology for peaceful purposes.

North Korea chief negotiator Kim Kye-gwan insisted his country should enjoy the right to peaceful use of nuclear energy.

Speaking to reporters outside the North Korea embassy following Thursday night's meeting of delegation heads, Kim expressed dissatisfaction with the United States' opposition to the North Korea's peaceful use of nuclear technology.

"The North Korea is neither a defeated nation in a war nor a nation having committed any crimes, so why should we not be allowed to use nuclear energy peacefully?" said Kim, also vice foreign minister of the North Korea.

However, Hill said that past experiences showed that the North Korea's nuclear facilities, even if they were used for civilian or research purposes, could be turned into "a weapon producing facility" in "two months."

Hill told reporters Friday morning that the ongoing six-party talks are "getting very much to the end," but negotiators still have "real differences".

"The good news is we knew where the substantive differences are...so we really like to try to reach an agreement on principles."

Hill said the US stance is closer to China, the South Korea, Russia and Japan. "We'll see if we can be closer to the North Korea."

As for the content of the common document, Hill said it was possible that the verification of the North Korea's nuclear facilities and programs would be included in the text.

Japanese delegation head Kenichiro Sasae said that all sides are making the final efforts to institute a joint document.

Russian chief delegate Alexander Alexeyev said the six delegations had reached consensus on 95 percent of the contents of the proposed common document, and were having a heated debate on the remaining 5 percent.

He said all the six parties wished to find a solution that satisfies every one concerned. "But this is not an easy task."

No chief negotiators' group meeting was held on Friday.

(Xinhua News Agency August 6, 2005)