The discovery of Cyrillic characters was disclosed in a long-awaited report today that also said there was “clear and compelling evidence” that they carried the nerve agent Sarin.
Russia is a strong ally of Bashar al-Assad and the disclosure came as Moscow was at loggerheads with the West over how to ensure the brutal dictator gives up his chemical arsenal.
Unveiling the report, UN chief Ban Ki-moon said that the attack in the capital Damascus was a war crime and the worst chemical weapons strike for 25 years.
“This was a grave crime and those responsible should be brought to justice,” he said.
The report stopped short of blaming Assad but Britain and France seized on it as fresh evidence that the tyrant was responsible for the August 21 attack that killed hundreds.
Foreign Secretary William Hague said that the “very damning” findings were “fully consistent” with Britain’s view that Assad and his henchmen were behind the atrocity.
“We have always believed that this was the work, the responsibility of the Assad regime and everything we can see in this report is fully consistent with that.”
He was speaking after talks with US Secretary of State John Kerry and his French counterpart in Paris.
The allies are pushing for a UN resolution that would authorise military action if the dictator went back on his promise to surrender his chemical weapons stockpiles.
Mr Kerry said the UN resolution had to be “forceful, accountable, transparent and timely”.
And he claimed that all the countries involved, including Russia, had agreed that military intervention could be an option “should diplomacy fail”.
“The framework fully commits the United States and Russia to impose measures under Chapter VII of the UN charter in the event of non-compliance.”