Russia criticizes U.S. refusal to fight rebels jointly in Syria

Russia said on Friday it hadintensified airstrikes against oil sites controlled by an al-Qaeda affiliate in Syria, but criticised the United States forrefusing to join in.

Last Friday Russia proposed to the United States and itsallies that they stage joint airstrikes on Syrian rebels,including the militant Islamist Nusra Front, who are notobserving a ceasefire, but Washington made clear it had littleinterest in the idea.

"The response received from the United States does notenvisage joint actions against terrorist organizations, whichleads to further escalation of the conflict," Sergei Rudskoy,head of the general staff's main operations command, told a newsbriefing.

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Meanwhile, the Nusra Front has partially restored itsfighting efficiency, replenished stocks of weapons andammunition and begun active military actions, Rudskoy said.

He said it was taking advantage of a previously announcedcessation of hostilities in many locations, and of the fact thatits units are often deployed in the same areas as the moderateopposition.

"Unfortunately, our American partners are not taking anydecisive steps apart from persistent requests not to strike thegroups of the Nusra Front, because 'moderate opposition' unitsmay be located nearby," Rudskoy said.

After discussing with U.S. experts the need to undermine theeconomic potential of the jihadists, Russian planes intensifiedstrikes from May 20 against Nusra's oil production sites andsmuggling routes to Turkey, Rudskoy said.

But the key question remains unsolved, he said.

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"Further delays by our American partners in resolving theissue of differentiating the opposition units it controls fromterrorists leads to the disruption of the peace process andresumption of military actions in Syria."

Washington has consistently refused to join forces withRussia in Syria ever since Moscow launched its campaign of airstrikes in September last year, accusing it of acting solely toprop up Syrian President Bashar al-Assad.