Rice: 'N Korea escalating crisis'
Ms Rice is on a four-day regional tour for talks on the crisis.
US Secretary of State Condoleezza Rice, has accused North Korea of wanting to escalate international tensions over its nuclear weapons programme.
Mr Rice said she doubts claims that North Korean leader Kim Jong-il agreed not to carry out a second nuclear test or that he regretted the first.
Her comments follow media reports that Mr Kim made the pledge to Chinese envoy Tang Jiaxuan when he visited Pyongyang.
She is in Moscow for talks expected to focus on the North Korea crisis.
Ms Rice is on a regional tour, meeting leaders in Japan, South Korea, China and Russia.
The secretary of state was in Beijing on Friday, but she said the Chinese made no mention of Mr Kim agreeing to halt nuclear tests, despite giving her a "thorough" briefing on Mr Tang's visit to Pyongyang.
"I don't know whether or not Kim Jong-il said any such thing," Ms Rice told journalists accompanying her on a flight from Beijing to Moscow.
"Tang did not tell me that Kim Jong-il either apologised for the test or said that he would not ever test again," Ms Rice added.
Though it is not confirmed, we have obtained information that... the country won't conduct a second nuclear test
"The North Koreans, I think, would like to see an escalation of the tension."
Mr Tang, a former Chinese foreign minister, was sent to North Korea on Thursday to deliver a personal message from President Hu Jintao.
Mr Tang did not set out what took place during his meeting with Mr Kim, but said afterwards that the visit had "not been in vain".