Breaking News Emails

Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.
 / Updated 
By Abigail Williams and Alexey Eremenko

The United States said Thursday it's "deeply concerned" by Russia's announcement of a "large-scale humanitarian operation" with the Syrian government in the besieged city of Aleppo.

Russian Foreign Minister Sergey Shoigu said three corridors would be opened for civilians to exit Aleppo, along with one corridor where Syrian opposition fighters would be encouraged to lay down their arms in exchange for amnesty and pardons.

Smoke rises over the Saif Al Dawla district of Aleppo, Syria, in October 2012.AP

"Without further clarification, this appears to be a demand for the surrender of opposition groups and the evacuation of Syrian civilians from Aleppo," State Department spokesman John Kirby said.

"Our position on humanitarian access has not changed. Russia and the regime must uphold the basic agreed principle that the U.N. determines what assistance is necessary to relieve the suffering of civilians in besieged communities," Kirby said.

Kirby said he wasn't aware of any consultation with the Washington on the operation. Any offensive operation would be "inconsistent with the spirit and the letter" of U.N. resolutions and with Washington's understanding with the Russians.

Children peer from a partly destroyed home in Aleppo, Syria, in February.Alexander Kots / AP

But Shoigu, the Russian foreign minister, insisted that the operation was "exclusively to ensure security of Aleppo residents."

The disagreement comes just week after Secretary of State John Kerry announced that the United States and Russia had reached an agreement to work together in Syria to stop the fighting and "create the space for a genuine and credible political transition."

Kirby said Thursday that the United States was "reconsider[ing] where we are" after the announcement, but he said discussions were continuing.

"As the secretary said himself, the proof's going to be in the pudding here," he said.