"The United States believes that Russia is responsible for the attack on two people in the United Kingdom, using a military-grade nerve agent," Haley said in New York.
Former spy Sergei Skripal and his daughter Yulia are in critical condition in the hospital after being poisoned in Salisbury with what British authorities have identified as the Soviet-era nerve agent Novichok.
Read more: Sergei Skripal case adds to West's 'massive trust deficit' against Russia
US President Donald Trump had pledged support to Britain and urged Russia to cooperate, but he did not suggest Russian culpability in the attempted murders.
Russia's ambassador to the UN reiterated Moscow's denial of any involvement in the attack. "Russia had nothing to do with this incident," Vassily Nebenzia said. "We have nothing to fear, nothing to hide."
Nebenzia said British Prime Minister Theresa May was creating a "hysterical atmosphere" when she said it was "highly likely" Russia was behind the attack and demanded information from Moscow about how a Cold War nerve agent was used in England.
"We do not speak the language of ultimatums," Nebenzia said. He called on Britain to hand over samples of the nerve agent for analysis, and provide "material proof" of "the allegedly found Russian trace."
'No alternative conclusion'During Wednesday's emergency meeting, Haley called on the UN to hold permanent council member Russia accountable.
"It must account for its actions," she said. "If we don't take immediate, concrete measures to address this now, Salisbury will not be the last place we see chemical weapons used."
Read more: Russian press slams UK, West in nerve agent attack coverage
British Deputy Ambassador Jonathan Allen appealed to Security Council members for support.
He said there was "no alternative conclusion than that the Russian state was responsible for the attempted murder of Mr. Skripal and his daughter."
He added that Russia was in breach of the chemical weapons convention for not declaring the Novichok program. "This was a reckless and indiscriminate act that put at risk the lives of civilians."
British Prime Minister Theresa May said this week it was "highly likely" Moscow was behind the attack. On Wednesday, May announced that the UK would expel 23 Russian diplomats after a Tuesday deadline for Moscow to provide an explanation was ignored.
nm/sms (Reuters, AFP)
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