Photo/Illutration A photo, center top, showing North Korea's missile launch is displayed at the Unification Observation Post in Paju, South Korea, near the border with North Korea, on Dec. 25. (AP Photo)

UNITED NATIONS--U.N. Security Council members are due to meet informally on Monday for a second round of negotiations on a Russian and Chinese proposal to lift a raft of sanctions on North Korea, a move that some diplomats say has little support.

China and Russia are convening negotiations a day before North Korean leader Kim Jong Un's deadline for the United States to show flexibility in stalled talks aimed at getting Pyongyang to give up its nuclear weapons program. North Korea has warned the United States could receive an unwanted "Christmas gift" if it fails.

A top White House official said on Sunday that the United States would be very disappointed if North Korea tested a long-range or nuclear missile and would take appropriate action as a leading military and economic power.

Pyongyang has been under U.N. sanctions since 2006 over its missile and nuclear programs, which the Security Council has unanimously strengthened over the years. Though some diplomats, speaking on condition of anonymity, have warned that unity would be broken if Russia and China put their new plan to a vote.

Russia and China proposed a draft U.N. Security Council resolution earlier this month that would lift sanctions on industries that earned North Korea hundreds of millions of dollars. Those sanctions were imposed in 2016 and 2017 to cut off funding for Pyongyang's nuclear and missile programs.

In an attempt to preserve council unity on North Korea, diplomats said the United States put forward a draft press statement on the issue, but that move was dismissed by Russia and China. The pair have instead scheduled on Monday a second round of talks on their draft resolution, diplomats said.

One Security Council diplomat, speaking on condition of anonymity, accused Russia and China on Sunday of coordinating with North Korea on the draft resolution, including letting Pyongyang make its own additions to the text, before they engaged with the 15-member Security Council.

"China and Russia are pushing a sanctions-gutting resolution knowing full well from the beginning that they do not have the votes for the resolution to pass," said the council diplomat.

"The U.N. Security Council cannot support a resolution that subsidizes DPRK's ongoing development of weapons of mass destruction with sanctions relief, which is what the Chinese and Russian resolution would do," the diplomat said, referring to North Korea's official name - the Democratic People's Republic of Korea.

Russia and China have said they hope lifting some sanctions could help break the deadlock and encourage talks between Washington and Pyongyang. But the United States, France and Britain said now is not the time to consider lifting sanctions.

A Security Council resolution needs nine votes in favor and no vetoes by the United States, China, Russia, France and Britain.

The Chinese and Russian proposal would lift a ban on North Korea exporting statues, seafood and textiles, and ease restrictions on infrastructure projects and North Koreans working overseas, according to the draft seen by Reuters.