Russia is killing innocent civilians under the false garb of counterterrorism operations in Syria, where people in an enclave near Damascus are caught up in a struggle between rebels and government forces, the White House has said.
The bombings and shellings by Syrian and Russian aircraft in Eastern Ghouta, the besieged rebel-held enclave on the outskirts of Damascus, continued despite a UN Security Council resolution demanding a 30-day ceasefire.
Over 600 people have been killed in the strikes since February 18.
"Russia has gone on to ignore its terms and to kill innocent civilians under the false auspices of counterterrorism operations," White House Press Secretary Sanders said in a statement on Sunday.
"This is the same combination of lies and indiscriminate force that Russia and the Syrian regime used to isolate and destroy Aleppo in 2016, where thousands of civilians were killed," she said.
Sanders blamed Tehran along with Moscow over the deteriorating conditions in Syria. "The US condemns the ongoing military offensive that the Assad regime, backed by Russia and Iran, is perpetrating against the people of Eastern Ghouta," Sanders said.
Meanwhile, US President Donald Trump and British Prime Minister Theresa May spoke about Syria and agreed the situation is a "humanitarian catastrophe" for which blame rests with Syria and Russia, according to May's office.
"They agreed that Russia and others with influence over the Syrian regime must act now to cease their campaign of violence and to protect civilians," the British readout said.