Russia's proposal for a new, joint investigation into the poisoning of an ex-spy and his daughter in England has been voted down at the international chemical weapons watchdog at The Hague.
Russia has accused Britain of blocking access to an investigation being carried out by the Organization for the Prohibition of Chemical Weapons (OPCW).
Britain earlier said Russia's call for an inquiry with the UK was "perverse".
Russia lost the vote by 15 votes to six, while 17 member states abstained.
China, Azerbaijan, Sudan, Algeria and Iran were among the countries that backed Russia's motion at the OPCW executive council, Reuters reported.
Russia called the meeting to challenge the UK, which has blamed Moscow for the March 4 poisoning of Sergei Skripal and his daughter Yulia in Salisbury, southern England.
Russia has strongly denied any involvement and in a press conference after the vote said what happened in Salisbury looked like a "terrorist attack". It strongly criticised the US and EU countries for siding with the UK.
The votes backing Russia and the abstentions showed that more than half of the council "refused to associate themselves with the West's point of view," said Russia's ambassador to the OPCW Aleksander Shulgin,
He said the UK had told the council "a dirty flow of complete lies... outright Russophobia".
At the Hague meeting, UK acting representative John Foggo had said the victim of a chemical weapons' attack was not required to work with the "likely perpetrator". Foreign Secretary Boris Johnson later accused Russia of trying to undermine the watchdog's work and said the international community had "seen through these tactics".
The British government says a military-grade Novichok nerve agent of a type developed by Russia was used in the attack.
The incident has caused a major diplomatic fallout, with the expulsion of some 150 Russian diplomats by the UK and its allies being met by counter-expulsions by Moscow.
On Tuesday the UK's Porton Down laboratory said it could not verify the precise source of the Novichok nerve agent used in Salisbury, although it did say it was likely to have been deployed by a "state actor".
The comments were seized upon by Russia to discredit the UK's accusations. It has requested that the UN Security Council meet on Thursday to discuss the situation for a second time.
At The Hague on Wednesday, the European Union offered its full support to Britain and reiterated that it backed the UK's assessment that it was "highly likely" that Russia was responsible.
British envoy Mr Foggo told the emergency OPCW meeting that the UK had blamed Russia based on:
- the identification of the nerve agent used
- knowledge that Russia "has produced this agent and remains capable of doing so"
- Russia's record of conducting state sponsored assassinations
- The assessment that Russia "views defectors as suitable targets for assassination"
He said that Russia had offered more than 24 "contradictory and changing counter-narratives" about the attack, including "preposterous" suggestions that Sweden, the US or Britain itself could have been responsible.
Russia's President Putin, speaking in the Turkish capital Ankara, said he hoped "common sense" would prevail.
What was the OPCW meeting about?
Russia called the meeting to confront Britain and to propose a new joint investigation with the UK into the Salisbury attack.
Western powers portrayed the bid as an attempt to undermine the OPCW's existing investigation. The global watchdog is analysing samples from Salisbury in order to identify the nerve agent used. It was asked to do so by the UK, and Russia was not invited to participate.
The OPCW expects to receive the results of its independent laboratory tests within a week. Russia has signalled it will reject the results of the investigation if its experts are prohibited from taking part.
The watchdog does not have the power to attribute blame, but it could ask the Kremlin to grant its inspectors access to former Soviet Union production facilities to check all of their chemical weapons stockpiles have been destroyed.
Did the UK already have a sample of Novichok?
Analysis by the BBC's David Shukman
The only way that scientists can be totally sure who made the Novichok agent is to compare it with another sample of the substance made in the same lab. That's what happened when Sarin was used by Saddam Hussein in Iraq and more recently by President Assad in Syria.
Experts already knew which clues to look for, and that allowed them to lay the blame definitively. Novichok is much less well known. The traces of it gathered in Salisbury will have been put through detailed scientific screening and that would reveal the ingredients of the chemical and maybe also its basic structure.
That could be matched with whatever is known about Novichok, maybe from lab notes handed over by defectors. And for Porton Down to describe it as "military grade" suggests a sophisticated state producer, not an amateur, though that itself is not categorical proof of Russian involvement.
That leaves another scenario in this secretive world of smoke and mirrors - that Britain did already have a sample of Novichok and was able to compare it to the agent used on the Skripals but does not want to reveal the fact, to protect a valuable source of intelligence.
Is the UK under pressure?
Questions arose about whether the UK had been too quick to point the finger at Russia after the Porton Down laboratory said that it could not verify the precise source of the Novichok nerve agent.
The laboratory said it was likely to have been deployed by a "state actor" but that it was not its job to say where the agent was manufactured.
Porton Down's chief executive Gary Aitkenhead dismissed Russian claims it might have come from the UK military laboratory.
On Twitter, the Russian Embassy highlighted a now-deleted tweet by the UK Foreign Office which suggested Porton Down had said the nerve agent had been produced in Russia.
22 March: “Porton Down lab @dstlmod clearly established that the source of Salisbury toxic agent was Russia”— Russian Embassy, UK (@RussianEmbassy) April 4, 2018
3 April: “ @dstlmod never had the task to establish the source of the toxic agent” pic.twitter.com/rVyJsbNJiG
The Foreign Office said the tweet had been part of a real-time account of a speech by the UK's ambassador in Moscow and was deleted because it "did not accurately report our Ambassador's words".
Security Minister Ben Wallace dismissed suggestions the government had been giving out mixed messages.
"Unlike Russia, we allow the media to come and meet our scientists and question the science," he said. "That's important. That's why we have this debate today: we have nothing to hide."
UK Labour leader Jeremy Corbyn has criticised Boris Johnson, suggesting he exaggerated evidence provided by Porton Down.