Russia and Jordan have agreed to "coordinate" military operations in Syria, Russia's Foreign Minister Sergei Lavrov said on Friday after meeting his Jordanian counterpart.

The announcement came just three weeks after Russia began a bombing campaign in war-torn Syria in support of President Bashar al-Assad.

"The armed forces of the two countries, the Russian and Jordanian forces, agreed to coordinate their actions, including those of their air forces over Syria," Lavrov told journalists in Vienna, adding that a "mechanism" had been set up in the Jordanian capital to facilitate cooperation.

The scope of the two countries' military cooperation was not immediately clear.

Russia's top diplomat also said that Moscow would back talks between Assad's government and the "full spectrum" of the Syrian opposition.

"Our common position is that we need to boost efforts for the political process in the Syrian settlement," Lavrov said.

"This foresees the start of full-scale talks between representatives of the Syrian government and the full spectrum of the Syrian opposition, both domestic and external -- with the support of outside players."

Jordan is a member of a US-led coalition that is targeting insurgents from the ISIS group in neighbouring Syria.

Russia is currently carrying out its own bombing campaign there at Assad's request, targeting ISIS militants and other "terrorist" groups.

The US and its allies have criticised the Russian strikes and accused them of mainly hitting anti-Assad rebels, while Moscow has blasted Washington for not sharing intelligence.

Standing next to Lavrov, Jordan's Foreign Minister Nasser Judeh said both sides' involvement in Syria meant there was a need for "close coordination.. particularly between the militaries on both sides".

"I hope this mechanism will be effective in fighting all terrorism in Syria and beyond," he told journalists.

Moscow has agreed limited coordination with Washington to avoid accidents as both their air forces are operating over Syria.