Russia warned Syria on Tuesday not to use chemical weapons, saying Moscow "proceeds from the assumption" that the government will adhere to its international obligations.
In a statement, the Russian Foreign Ministry said Syria had ratified an international protocol in 1968 that bars the use of poison gases as a method of warfare.
Syrian Foreign Ministry spokesman Jihad Makdissi acknowledged on Monday that the country had chemical weapons, saying it would not use them to crush rebels but could use them.
Later on Tuesday, Russia's ambassador to the UN Vitaly Churkin told Charlie Rose: "Assad is not our stooge, waiting for phone call from Moscow telling him what to do. He represents an entire power structure which needs to be reformed in order to satisfy the aspiration of the entire Syrian people, also, in a way not to offend and put at a considerable disadvantage the segment of the population he represents."
Also on Tuesday, an Iranian semi-official news agency quoted the commander of Iran's powerful Revolutionary Guards as warning "hated Arab" rivals that they could face repercussions for their efforts to topple the Tehran-backed regime of President Bashar Assad in Syria.
Gen. Masoud Jazayeri did not specify any country or give details on the type of possible backlash, but Iran's main Arab foe Saudi Arabia and other Gulf nations such as Qatar are key supporters of the Syrian rebels.
The comments, carried by the semiofficial Fars news agency, also appear aimed at dismissing speculation that Iran is trying to distance itself from Assad as part of political bet-hedging in case he falls. Assad is Iran's main Middle East ally, and his downfall would be a serious blow to Iran and its proxy forces Hezbollah in Lebanon and Palestinian Hamas.
"Soon the soil of Syria will be cleaned of the dirt of the enemy," Fars quoted Jazayeri as saying.
He added the "resistance" meaning Assad's government and its allies "will settle scores with enemies one by one."
Jazayeri, also a spokesman of the Joint Chiefs of Staff, said that Assad's regime has friends in the region poised to "strike out" an apparent reference to forces that include Hezbollah and Hamas.
"Yet none of the friends of the Syrian government and the great front of resistance has entered the scene. If this happens, they will strike back hard at the enemy, particularly the hated Arabs," Jazayeri was quoted as saying.
The remarks suggest that Iranian has no current military role in the Syrian crisis despite close relations between Tehran and Damascus.
Iran has proposed playing a mediator role between Assad and rebels, but the offer has found no backing among opposition groups that refused to negotiate to Assad or allies. At least 17,000 people have died in the Syrian uprising since March 2011.
Gulf nations such as Saudi Arabia and Qatar have pledged funds to aid
Syria's rebels, but there is no clear trail showing how much is reaching the fighters.
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