The US says it has been "encouraged" by signs that North Korea has agreed to multilateral talks on its nuclear weapons programme.
The news may ease the tension between North Korea and the US
"We're very encouraged by indications that North Korea is accepting our proposals for multilateral talks," said state department spokesman Richard Boucher.
He was speaking after Russia announced the North had reversed its long-standing demand for one-on-one talks with America.
US President George W Bush earlier reported that progress was being made after a telephone conversation with his Chinese counterpart, Hu Jintao.
"I'd say the news that's out of Moscow is all consistent with the conversation that President Hu and President Bush had yesterday," Mr Boucher said on Thursday.
The developments come, however, after a fierce verbal attack on North Korea by US arms negotiator John Bolton, who is on a three-nation tour of Asia.
Pyongyang, he said, had accelerated its nuclear weapons programme while its people lived a "hellish nightmare" under the "tyrannical dictator" Kim Jong-il.
Russia, which along with China is one of the few states with close ties to North Korea, said it had agreed to six-nation multilateral talks, without specifying the nations involved.
The Russian foreign ministry said the message was delivered by North Korea's Ambassador to Russia, Pak Ui Chun.
"On behalf of his leadership, the ambassador said [North Korea] favours holding six-sided talks with Russia's participation on settling the current
difficult situation on the Korean peninsula and is undertaking active efforts for them to take place," the ministry said.
The six states are believed to be North and South Korea, Japan, China, Russia and the US.
Last week, after consultations in Washington, China delivered America's request for multilateral talks to Pyongyang.
If confirmed, the North Korean move will be a significant development in the ongoing row which flared up in October, when the US said North Korea had admitted having a secret nuclear programme.
The BBC's Nikolai Gorshkov says there was a sigh of relief in Moscow, which has been increasingly concerned over the stand-off between Pyongyang and Washington.
Russia was nervous of an all-out showdown between the two, with authorities in the country's Far East preparing for the worst and putting their civil defences on alert.
Now Russia will seek to play the mediator to reconcile US apprehensions about the North's nuclear programme with Pyongyang's demands for guarantees of its security, our correspondent adds.