MOSCOW - Top U.S. nuclear envoy Christopher Hill said Friday that the next round of six-party talks on North Korea's nuclear program could take place this month, the ITAR-Tass news agency reported.

Hill's visit to Russia came amid concern over North Korea's failure to meet a year-end deadline for a full declaration of its nuclear activities.

Speaking to reporters after his talks with Russian Deputy Foreign Minister Alexander Losyukov, Hill emphasized the need for North Korea to quickly produce the declaration.

"What we need is a clear and complete declaration on the nuclear facilities," Hill said. "They are obliged to get a complete and correct declaration."

In Beijing on Thursday, Hill said North Korea may be delaying a full accounting for fear of revealing hidden programs that would invite further scrutiny.

The North said last week it had already provided the United States with the declaration, but Washington says Pyongyang has not yet given a complete accounting.

North Korea was promised the equivalent of almost one million tonnes of oil and political concessions at six-party disarmament talks in return for disabling and declaring its nuclear programs. The United States has also said it would remove the North from terrorism and sanctions blacklists.