The UN Security Council expects to impose arms and financial sanctions on North Korea on Saturday for its reported nuclear weapons test, with US intelligence pointing to confirmation that it took place.
Russia and China submitted new amendments to a US- drafted UN resolution, which are expected to delay the vote by several hours, but US Ambassador John Bolton said he was confident the resolution would be adopted on Saturday.
In Washington, a preliminary US intelligence analysis has shown radioactivity in air samples collected near a suspected North Korean nuclear test site, a US official said on Friday, five days after Pyongyang announced it conducted the test.
"That's right, though this is only a first look. People have been saying all along that the working assumption is it was a nuke," said the official, who spoke on condition of anonymity.
At the United Nations, Bolton said on Friday evening that weapons-related "technical" amendments had arrived from Moscow, which council members were studying.
"I'm still ready to go for a vote. We will just have to see what the instructions are overnight in particular from Moscow and China," Bolton said. "It is late in the process and the imperative for swift action because of the North Korean nuclear test remains."
Seeking to meet objections from China and Russia, the latest version of the US-drafted resolution makes clear the measures do not include military force under Chapter 7 of the UN Charter. The resolution has never threatened force but China wanted to make sure the measure would not be used to justify military action against North Korea.
On Friday, China's UN ambassador, Wang Guangya, voiced reservations about the most controversial provision in the text that authorises nations to search cargo going to and from North Korea for nuclear materials or ballistic missiles.
China wants the wording softened to make interdiction less mandatory in the resolution, while Russia has criticised other parts of the text.
"We are not at the final text yet," Wang said.
The draft UN resolution would prohibit the transfer or development of weapons of mass destruction and ban sales of luxury goods to North Korea. It would freeze funds overseas of people or businesses connected with Pyongyang's nuclear and ballistic missile programs.
It also imposes an arms embargo on heavy conventional weapons and allows a travel ban on individuals connected with North Korea's dangerous weapons programs, and their families, if a council sanctions committee approves the names.