Russia on Wednesday condemned the "tragic" killing of a US war correspondent and French photojournalist in the Syrian flashpoint city of Homs.

The foreign ministry said "Moscow resolutely condemns and is seriously concerned" by the Western journalists' slaying.

"This tragic event once again confirms the need for all the sides of the Syrian conflict to end the violence and move toward a political course with the start of an all-encompassing national dialogue without preconditions."

Russian Deputy Foreign Minister Gennady Gatilov separately told reporters that it was premature to blame President Bashar al-Assad's forces for the deaths because both sides of the conflict were resorting to violence.

Gatilov noted that Arab observers had blamed last month's death in Homs of French television reporter Gilles Jacquier on the armed opposition.

Veteran US war correspondent Marie Colvin of Britain's Sunday Times and freelance French photojournalist Remi Ochlik were killed Wednesday when a makeshift media centre in Homs came under attack.