Neither Russia or China want to see Iran possessing nuclear weapons. A year ago the Bush administration was the problem preventing an agreement on sanctions. That problem is gone and the situation has drastically changed. Iran needs to sell oil more than China needs to import it now. Russia is blocking the startup of the Busherh reactor and balking at delivering the S-300MPU-1s Iran has contracted for. Expect sanctions in the next day or two.
U.S.-led coalition conducts 13 airstrikes against ISIS targets in Syria, Iraq (Reuters)
from the article: Medvedev to European Jewish Congress: Iran threat very real