Poland's foreign minister on Friday said Russia was responsible for Syria's Soviet-era chemical weapons and could use its clout to impact the course of the country's conflict.
"Russia keeps stressing that it is against the use of chemical weapons, but we know the Syrian arsenal dates back to the days of the USSR. It's Soviet technology," Foreign Minister Radoslaw Sikorski told reporters in Warsaw.
"I think that if Russia were to say that it will assure control over Syria's arsenal of chemical weapons, it could have an effect on how the situation develops."
The United States and allies such as France are in favour of a military intervention against the Syrian regime, which they accuse of using chemical weapons in attacks outside Damascus that activists say killed hundreds of people last week.
Russia for its part said military action without UN approval would deal a major blow to the existing world order and was unlikely to bring stability and calm to its ally Syria and the Middle East as a whole.
Moscow has repeatedly used its veto power on the UN Security Council to block action against the Syrian regime.
Polish Prime Minister Donald Tusk on Wednesday said Warsaw would not take part in a military intervention.
"I'm not convinced an armed attack will stop the crimes," he said in a rare departure from toeing the same line as the United States.
Poland was a major contributor of troops for the US-led wars in Iraq and Afghanistan, where it still maintains 1600 soldiers.
But its president said earlier this month that the EU member would limit its participation in overseas military missions and concentrate on modernising its forces at home.