Russian President Vladimir Putin on Saturday dismissed claims that the Syrian regime has used chemical weapons, demanding that the United States provide proof rather than taking rash action.
Speaking after the United States released an intelligence report, Putin rejected US use of intercepts of Syrian communications as evidence, saying that they could not be used to take "fundamental decisions" like using military force on Syria.
And he rubbished the notion that the Syrian army used chemical weapons, saying to do so would defy "common sense."
"Syrian government troops are on the offensive and have surrounded the opposition in several regions," he said in the Far Eastern city of Vladivostok.
"In these conditions, to give a trump card to those who are calling for a military intervention is utter nonsense."
Russia, Syria's vocal and powerful ally, has vowed to block any action against the regime of Syria's Bashar al-Assad in the UN Security Council, where it is a permanent member.
Putin said he was sure the alleged attack was "nothing but a provocation" by those who want to drag other countries into the Syrian conflict, and demanded proof this was not the case.
"Regarding the position of our American colleagues, friends, who affirm that government troops used weapons of mass destruction, in this case chemical weapons, and say that they have proof, well, let them show it to the United Nations inspectors and the Security Council," he said.
Saying that such evidence is classified "does not stand up to criticism" and disrespects other countries, Putin said. "If there is evidence, it must be presented. If they don't show it, that means there is none."
Signup to our newsletter and follow us on Facebook and Twitter!
"Talk that these are once again some kind of intercepts of some kind of communications that don't prove anything cannot be used as a basis for such fundamental decisions like using force against a sovereign state," he said.
It was Putin's first public reaction to the US assertion that the Syrian government used chemical weapons in the suburbs of Damascus on August 21, killing 1,429 people.
US President Barack Obama has called the alleged attack "a challenge to the world", and said he is considering a "limited, narrow act", while stressing no final decision has been taken on unleashing military strikes against the regime.
Putin, who said he had not discussed Syria with Obama since the alleged attack, called on the US leader not to initiate another military conflict, citing action in Afghanistan, Iraq, and Libya.
"Would it be in the interest of the US to yet again damage the international security system, the foundations of international law? Would it strengthen the international prestige of the US?" Putin said, asking that decisions on military action be taken "without haste".
The Kremlin has said Putin is not planning to meet Obama separately at the summit since Washington scrapped the US President's plans for a state visit to Moscow ahead of the G20.
Russia's foreign ministry said that the US ambassador to Moscow presented the US case against Syria to deputy foreign minister Sergei Ryabkov on Saturday and was told that any use of force would be "an act of aggression."
Russia had also welcomed Friday's rejection by the British parliament of military action against the Syrian regime.
"Over the last few years, everyone, including me, has gotten used to the Western community deciding things without much discussion... and according to the wishes and position of the main partner, the United States," Putin said.
"If this time there is some kind of glitch, to me that is unexpected" and "shows that even in Britain... there are people that rely on national interests and common sense and value their sovereignty," he said.