Russia is holding up Security Council approval of a proposed new international body to assign blame for chemical attacks in Syria's deadly conflict for the first time.

Russia's U.N. Ambassador Vitaly Churkin, who holds the council presidency in September, told reporters Wednesday that Russia had questions about the proposal by U.N. Secretary-General Ban Ki-moon.

Ban sent a letter to the council last Thursday recommending the establishment of an independent panel backed by experts with the freedom to go anywhere in Syria to determine who is using chlorine and other chemical weapons. The council was to respond in five days.

Churkin said Russia wants clarifications it was given by the U.N. Secretariat to be put in writing and hopes this can be done very quickly.