The United States would consider talks with North Korea if it halts all nuclear and ballistic missile tests, Washington's envoy to the United Nations said Tuesday as the UN Security Council considered new sanctions on Pyongyang.

"We are willing to talk but not until we see a total stop of the nuclear process and of any test there," the US envoy, Nikki Haley, told reporters.

Washington and Beijing -- the North's sole diplomatic and military ally -- are working on a new Security Council sanctions resolution targeting Pyongyang, she added.