The United States and China are moving forward in talks to adopt a new U.N. Security Council resolution imposing sanctions on North Korea for its nuclear and missile tests, the U.S. national security advisor said.

"China is obviously a critical player at the United Nations and it, too, has choices to make. We have had ongoing discussions with the Chinese in New York. President Obama has spoken to President Xi. I think these discussions are progressing," National Security Advisor Susan Rice said at a briefing Monday night, according to a pool report.

For more than a month, since the North's nuclear test, the Security Council has been struggling in negotiations to come up with a new sanctions resolution on the North because China has been reluctant to impose harsh measures on Pyongyang.

Amid the deadlock, the North flouted the Security Council again with a banned missile launch on Feb. 7.

Beijing has condemned the North's nuclear and missile tests but has been lukewarm about calls for a stern response. Analysts have long said Beijing fears that pushing Pyongyang too hard could lead to its collapse, instability on its border with China and ultimately the emergence of a pro-U.S. nation.

Chinese cooperation is key to any meaningful punishment as it is one of the five veto-holding permanent members of the U.N. Security Council and the main provider of food and fuel aid to the impoverished North.

"I think it unlikely that China wants to be seen by the international community as the protector of North Korea, given its recent outrageous behavior in violation of international law and U.N. Security Council resolution," Rice said.

She also said that North Korea is a topic of interest to the entire region and the U.S. will "continue our work to contain and reduce the threat posed by North Korea," adding that the issue will also be discussed at President Barack Obama's summit in California with the leaders of the Association of Southeast Asian Nations. (Yonhap)