Snowden, who exposed classified U.S. programs that collect telephone and Internet data, has been in Sheremetyevo airport's transit area since June 23.
It remains unclear how the world's most famous refugee would be able to leave the transit zone of Sheremetyevo Airport, where he has been marooned without valid documents since he arrived from Hong Kong on June 23.
Bolvia's Morales, referring to the U.S.: "We don't need them, we've got other allies."
Vladimir Putin, who has disagreed with the Obama administration on its handling of the Syrian conflict and plans to develop a missile-defense shield in Europe, tried to distance himself from the case.
At least 20 children killed, state medical examiner's office said.