"US-Russian coordination [in solving the Syrian crisis] is essential, but it's insufficient without other players — Iran, Saudi Arabia… Also it cannot be solved without Syrians themselves, without discussion between Syrians on a transitional government," Pickering said at a conference on Russia-US ties in Moscow.
Syria has been mired in civil war since 2011, with forces loyal to Assad fighting against numerous opposition factions and extremist groups, such as Daesh radicals, prohibited in a range of countries, including Russia.
In October, international talks on the settlement of the Syrian crisis started, bringing together many countries. During the second round of talks in the so-called Vienna format, negotiators called for elections in Syria to be held within 18 months.
