U.S. Ambassador to the United Nations Samantha Power said China has "often backed" Russia on "every relevant" action in the Security Council with respect to Syria in a Friday speech at Center for American Progress:
SAMANTHA POWER: [...] Russia, often backed by China, has blocked every relevant action in the Security Council, even mild condemnations of the use of chemical weapons that did not ascribe blame to any particular party. In a Assad's cost-benefit calcululus, he must have weighed the military benefits of using this hideous weapon against the recognition that he could get away with it because Russia would have Syria's back in the Security Council. [...]
Power's statement marks the first time the Obama administration has blamed China along with Russia for obstructing UN Security Council action on Syria.
As early as yesterday Power avoided bringing up China's backing of Russia in the Security Council, Josh Gerstein of Politico reports:
As American officials bitterly denounce Russia for blocking the United Nations from endorsing action over Syria’s alleged use of chemical weapons, another global power that has taken a similar stand seems to be getting a free pass from the U.S: China.
[...]
Speaking to reporters Thursday, U.S. Ambassador to the U.N. Samantha Power laid blame for the impasse regarding Syria squarely at the feet of the Russians.
"Even in the wake of the flagrant shattering of the international norm against chemical weapons use, Russia continues to hold the council hostage and shirk its international responsibilities, including as a party to the Chemical Weapons Convention," Power said.
She made no mention of China’s role, although that country, too, is a signatory to the anti-chemical weapons pact. State Department spokespeople did not respond to queries about whether the U.S. also views China as holding "hostage" the U.N. Security Council.
In fact, when a Security Council resolution offered by the British was blocked last week, it was the third time a Syria-related measure had been defeated. In each instance, Russia and China acted in lock step to prevent its adoption.