Russia on Wednesday announced the first international talks on the Syria conflict since Washington pulled out of bilateral ceasefire negotiations in protest at Moscow's bombing of Aleppo.
Foreign Minister Sergei Lavrov and US Secretary of State John Kerry agreed to sit down with top diplomats from "key countries in the region" on Saturday in Lausanne, the foreign ministry in Moscow said.
The meeting -- which Lavrov said could include Turkey, Saudi Arabia and possibly Qatar -- comes after Syria plunged into some of the worst violence it has seen as government forces backed up by Russian airpower push a brutal assault to take rebel-held eastern Aleppo.
Fresh air strikes and artillery fire in Aleppo on Wednesday left at least seven people dead, an international monitor said, a day after Russia was accused of stepping up its raids on the city.
The West has accused Moscow of potential war crimes over its bombing campaign, as acrimony surged after the US on October 3 pulled the plug on bilateral talks with Moscow after a truce deal unravelled.
Despite the collapse in relations Lavrov told CNN in an interview Wednesday that he hoped the weekend talks in Switzerland could help "launch a serious dialogue" based on the now-defunct US-Russian pact.
"We would like to have a meeting in this narrow format, to have a businesslike discussion, not another General Assembly-like debate," Lavrov said.
The United Nations said that Syria envoy Staffan de Mistura had been invited to take part in the talks but hopes were low of a breakthrough to end the five-year conflict that has claimed some 300,000 lives.
Punitive measures 
The fallout from the collapse in diplomacy on Syria has seen some in the West call for punitive measures against Moscow, while Russia has responded by bolstering its forces in the war-torn country.
President Vladimir Putin on Wednesday warned Western countries against imposing sanctions against Moscow over Syria, stressing that Russia would not let itself be isolated.
"We should not go down the path of pressure and blackmail but search for compromise," Putin said at an investment forum in Moscow.
"I have said one hundred times that we are ready to search for these compromises. We would very much like that our partners treat us this way."
Putin earlier this week cancelled a long-planned visit to France over Syria, and on Wednesday slammed Paris for tabling a UN proposal on Aleppo at the weekend that Russia vetoed.
"They put forward the resolution knowing that it would not pass... in order to incite a veto," Putin said.
"Why? It was aimed at inflaming the situation and fanning hysteria around Russia."
French Foreign Minister Jean-Marc Ayrault said that Putin had cancelled his visit because he was "embarrassed" about Russia's bombing of Aleppo.
The United Nations has warned of the unfolding humanitarian catastrophe taking place in besieged eastern Aleppo, saying that the rebel-held territory could be destroyed entirely by the end of the year.
Pope Francis appealed on Wednesday for an immediate ceasefire in Syria, calling for "at least" a truce enabling civilians, especially children, to be evacuated, after Aleppo came under fierce air assault.
"It is with a sense of urgency that I renew my appeal, begging those responsible, with all my strength, for an immediate ceasefire to be imposed and respected," the pontiff told his weekly audience in Saint Peter's Square at the Vatican.