The United States has said it is "skeptical" of a Russian announcement that it had opened humanitarian corridors in Aleppo, with Secretary of State John Kerry fearing a potential "ruse."
Russia, a key ally of the Syrian regime in the five-year war, announced Thursday several corridors for civilians and surrendering fighters to leave the northern Syrian city, which has been under heavy assault for weeks.
Besieged residents were cowering indoors, afraid to use what some called "death corridors."
Kerry -- who has spoken twice with Moscow in the past day and met with his Russian counterpart Sergei Lavrov on Tuesday in Laos -- said cooperation between Moscow and Washington could turn sour if the announcement proves deceitful.
"It has the risk, if it is a ruse, of completely breaking apart the level of cooperation," Kerry said. "On the other hand, if we're able to work it out today and have a complete understanding of what is happening and an agreement on the way forward, it could actually open up some possibilities."
The proposal raised concerns that the corridors could be used to flush out Aleppo before a final push by the Syrian regime forces to take the city.
"We are taking a look at Russia's announcement of humanitarian corridors, but given their record on this, we are skeptical to say the least," said White House Deputy Press Secretary Eric Schultz at a briefing.
The White House remains "deeply concerned about the situation in Aleppo," said Schultz.
"Over the last few weeks Russian and Assad regime offensive have offensively cut off the opposition held parts of the city. This only exacerbates the humanitarian situation by laying siege to some 300,000 civilians," Schultz said.
"Access to the city should be open to fully allow for unimpeded humanitarian support and commercial traffic to Syrian civilians in their homes.
