Russia has denied interfering with evidence at the site of a suspected chemical weapons attack in Syria which led to Saturday's military intervention by the US, the UK and France.
In an interview for BBC's Hardtalk, Russian Foreign Minister Sergei Lavrov said: "I can guarantee that Russia has not tampered with the site."
He spoke as the OPCW chemical weapons watchdog held an urgent meeting.
Inspectors in Syria have still not gained access to Douma, it is reported.
The UK ambassador to the OPCW (Organisation for the Prohibition of Chemical Weapons), Peter Wilson, quoted the organisation's director-general as saying they were still waiting.
The Swedish delegation cited a briefing from the director-general that said Syria and Russia were concerned that security on the ground could not be guaranteed.
The meeting in The Hague is behind closed doors but Reuters news agency reports that the American ambassador, Kenneth Ward, expressed concern the Russian forces there might have tampered with evidence.
The Russian foreign minister again denied the use of chemical weapons in Douma on 7 April.
"I cannot be impolite with the heads of other states but you quoted the leaders of France and the UK and US and, frankly speaking, all the evidence they quoted was based on media reports and social media."
The event did not take place, he said. "What did take place was the staged thing," he added.
Mr Lavrov also questioned why the US and its allies had carried out air strikes the day before international inspectors were due to arrive at the site.
On the air strikes, he repeated the Russian assertion that two-thirds of the more than 100 missiles fired into Syria on Saturday had failed to reach their targets.
Mr Lavrov said the "deconfliction channel" to prevent a clash between US and Russian forces had done its job and a confrontation had not been close.
But he added that Russia and the West were facing a situation worse than during the Cold War due to a lack of channels of communication between the two sides.
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