© RuptlyThe United Nations Security Council
Russia has requested an open session of the US Security Council on Thursday to discuss the accusations from the UK that Moscow used a nerve agent against former spy Sergei Skripal and his daughter in England last month.

The use of chemical weapons by anyone anywhere is "inadmissible and must be investigated and punished," Russia's ambassador to the UN Vasily Nebenzya wrote to the UNSC president, according to TASS. The council is currently chaired by Peru.

Nebenzya sent the request after the British Foreign and Commonwealth Office deleted the March 22 tweet in which it claimed experts at the chemical weapons laboratory at Porton Down confirmed the substance that allegedly poisoned Skripal and his daughter Yulia was "military-grade Novichok nerve agent produced in Russia."

While Porton Down was able to identify the substance as Novichok, the scientists there could not link the samples to Russia, executive Gary Aitkenhead told Sky News on Monday.

"We have not identified the precise source, but we have provided the scientific info to government who have then used a number of other sources to piece together the conclusions you have come to," Aitkenhead said.

The UK has refused to release any evidence tying Russia to the incident. Moscow has maintained that Russia had nothing to do with the alleged poisoning of the Skripals.

Sergei is a former Russian intelligence operative who was convicted of spying for the British in 2006 and sent to the UK in 2010 as part of a spy swap. His daughter Yulia is a Russian citizen, who came to visit him in Salisbury last month. Russian diplomats have been barred from visiting her in the hospital, in violation of diplomatic conventions. May's government expelled 23 Russian diplomats in March. The US, Canada, Australia and a number of NATO countries followed suit, expelling over 150 Russian diplomats that they accused of being spies.

Moscow has responded by expelling an equal number of diplomats from the countries involved, shutting down the British Council operations in Russia, and closing the US consulate in St. Petersburg to match the US closure of the Russian consulate in Seattle, Washington.