美国国务卿克里表示，在叙利亚问题上，美国及其盟友愿意考虑所有选项，但他也承认，尽管俄罗斯拒绝退让，美国和欧洲没有采取军事行动的意愿。
克里星期天与英国外交大臣约翰逊在伦敦会晤。星期六他还与俄罗斯外长拉夫罗夫和其他高级外交官在瑞士举行了会谈。
克里说，没有人应该给一场内战“火上浇油”，或是把两个超级大国推向对抗。
克里星期天说：“当一个超级大国卷入这样的战斗，就像俄罗斯所做的那样，在叙利亚部署导弹，以军事手段威胁那里的人民，这样做提升了冲突的可能性。”
克里显然对叙利亚的局势发展感到头痛，包括难民危机，阿勒颇平民被屠杀，俄罗斯为扶持阿萨德政府采取的军事行动，停火破裂，而华盛顿又显然无法阻止流血冲突。
他警告说，由于阿勒颇局势，可能对俄罗斯和叙利亚政府采取制裁。
克里还说，星期六在瑞士的谈判产生了一些提议，需要进一步商讨，但是他没有详细阐述这些提议是什么。
与此同时，土耳其外交部长星期天宣布，土耳其支持下的叙利亚反政府武装从伊斯兰国极端分子手中夺取了叙利亚北部具有象征意义的重镇达比克 。
Secretary of State John Kerry says all options remain open for the U.S. and its allies in Syria, but he admits the United States and Europe have no appetite for military action, even as Russia refuses to back down.
Kerry held talks in London Sunday with British Foreign Secretary Boris Johnson, a day after Kerry met with Russian Foreign Minster Sergei Lavrov and other top diplomats in Switzerland.
Kerry said no one should be "lighting a fire" under a civil war or pitting two superpowers against each other.
"When a great power is involved in a fight like this, as Russia has chosen to be by going there [ Syria } and then putting its missiles in place in order to threaten people against military action, it raises the stakes of confrontation," Kerry said Sunday.
Kerry has clearly been frustrated at what has been going on in Syria -- the refugee crisis, the slaughter of civilians in Aleppo, Russian military action on the side of the Assad regime, truce breakdowns and Washington's apparent impotence at being able to stop the bloodshed.
"It's a humanitarian disaster ... and it could stop tomorrow if Russia and the Assad regime were to behave according to any norm or standard of decency," Kerry said Sunday. "Instead we see what can only be described as crimes against humanity taking place on a daily basis -- when a hospital gets bombed, when children are bombed, when gas, which is outlawed by the chemical convention, is used against human beings in Aleppo or elsewhere in the country."
Kerry warned of sanctions against Russia and Syria over the situation in Aleppo.
He also said that Saturday's talks in Switzerland produced "several ideas that need to be quickly followed up." But he gave no details.
Also Sunday, Turkey's foreign minister announced that Turkish-backed Syrian rebels captured the symbolically important northern Syrian town of Dabiq from Islamic State.
