US Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov will return to talks in Switzerland on the Syria conflict.

The talks are expected to be the last hope for peace this year after a painstakingly-drafted ceasefire failed three weeks ago. Kerry has pointedly avoided new bilateral negotiations with Lavrov. UN Syria peace envoy Staffan de Mistura has offered to escort members of an Islamist militant group out of Aleppo if that would entice Damascus to forge a ceasefire with the remaining rebels.

Lavrov has said he does not plan to bring any fresh ideas to the new round of talks. But his deputy Gennady Gatilov said Russia wants to discuss de Mistura's offer.