US Secretary of State John Kerry and his Russian counterpart Sergei Lavrov are calling for "localised ceasefires" in Syria before peace talks this month in Switzerland.
Lavrov and UN-Arab League envoy Lakhdar Brahimi also say Damascus ally Iran should take part in the so-called Geneva II talks due to start in Montreux on January 22.
"We talked today about the possibility of trying to encourage a ceasefire, maybe a localised ceasefire beginning with Aleppo (north of Syria)," Kerry said following a meeting in Paris on Monday.
Kerry and Lavrov said they hoped ceasefires could be in place before the talks, along with plans for prisoner exchanges and the opening of humanitarian corridors.
"What can be done before the beginning of the conference should be done," Lavrov said.
"We are going to try to send signals to all the Syrian sides on the need for the establishment of a localised ceasefire."
Lavrov added, however, these issues would not be a precondition to the talks.
He reiterated Russia's support for Iran taking part in the peace talks, which has been repeatedly rejected by the US.
Kerry said Tehran could take part in the talks only if it agreed to the principles set out at the first Syria peace talks in Geneva, including the goal of creating a transitional government.
"Iran has yet to state whether or not it supports implementing the Geneva I communique," Kerry said.
"We would welcome Iran participating if Iran is coming to participate for the purposes of the conference.
"I invited Iran today to join the community of nations ... and be a constructive partner for peace," he said.
The Swiss talks have been organised to revive the idea of moving to a transitional government in Syria - where the nearly three-year conflict has killed 130,000 people - which would include figures from the present regime and the opposition.
The Syrian opposition has in the past called for President Bashar al-Assad to stop using heavy weapons, lift sieges on several opposition-held areas and allow the opening of humanitarian corridors as a show of good faith ahead of any talks - to no avail.
