Russia on July 6 objected to a U.S.-drafted resolution at the UN condemning North Korea's first-ever launch of an intercontinental ballistic missile.
Russia contends that the missile was medium-range and not long-range and said it was seeking a change to the resolution being debated by the UN Security Council.
Moscow's resistance to defining Pyongyang's missile launch as long-range does not bode well for Washington's hopes of pushing through stronger sanctions on Pyongyang, which U.S. Ambassador to the UN Nikki Haley said she will propose soon.
Moscow believes North Korea fired an intermediate range ballistic missile on July 4. The United States agrees with North Korea's claim that it was an ICBM and represented a major leap in technology over previous missiles tested.
"We cannot confirm that the missile can be classified as an ICBM," Russia's UN mission told other council members in an e-mail. "There is no consensus on this issue."
Russia's objection effectively blocks the resolution, as a consensus is needed to approve it.
Haley lashed out at Russia's move.
"If you need any sort of intelligence to let you know that the rest of the world sees this as an ICBM, I'm happy to provide it," she said.
She called the launch "a clear and sharp military escalation" and warned that Washington was ready to use military force, "but we prefer not to have to go in that direction."
Russian Deputy Ambassador Vladimir Safronkov warned that "any attempts to justify a military solution are inadmissible and will lead to unpredictable consequences for the region."
He also argued against tougher sanctions, saying they "will not resolve the issue."
"Attempts to economically strangle North Korea are equally unacceptable, as millions of North Koreans remain in need of humanitarian aid," he said.
Haley did not give details on what sanctions the United States would propose but outlined available options. North Korea has been under UN sanctions since 2006 over its ballistic-missile and nuclear programs.
"The international community can cut off the major sources of hard currency to the North Korean regime. We can restrict the flow of oil to their military and their weapons programs. We can increase air and maritime restrictions. We can hold senior regime officials accountable," Haley said.
Diplomats said Washington proposed such options to Beijing two months ago but that China only agreed to adding some people and entities to the existing UN sanctions list.
Following a nuclear weapons test by North Korea in September, while U.S. President Barack Obama was still in office, it took the UN Security Council three months to agree on stronger sanctions.
It was not immediately clear how long U.S. President Donald Trump's administration is prepared to negotiate with China and Russia over new measures.
Trump has threatened to use trade to pressure Beijing, North Korea's biggest trading partner, to do more to rein in its ally.
The United States unilaterally sanctioned Chinese companies doing business with North Korea earlier this year, and U.S. officials said more such sanctions may target Chinese companies, especially banks, in the future.
Trump earlier on July 6 had hinted at the possibility of a "pretty severe" response from Washington to the missile launch.
"I don't like to talk about what I have planned, but I have some pretty severe things that we are thinking about," he said. "That doesn't mean we are going to do them. I don't draw red lines."
He said North Korea is "behaving in a very, very dangerous manner and something will have to be done about it."
Trump and the leaders of Japan and South Korea agreed on the need for "more severe measures" against Pyongyang at a dinner before the Group of 20 summit in Hamburg, Germany, on July 6.
The three leaders had a "very vivid discussion" and discussed "the necessity for China to perform an even greater role" in carrying out sanctions against North Korea, said Norio Maruyama, press secretary for Japanese Prme Minister Shinzo Abe.
With reporting by AP, AFP, dpa, and Reuters