Russian Foreign Minister Sergei Lavrov said in a statement that a meeting in Moscow later on Tuesday between the foreign ministers of Iran, Turkey and Russia would adopt tangible measures on Syria.
Lavrov also condemned the murder of Russia's ambassador to Turkey Andrei Karlov on Monday, who was shot in the back and killed as he gave a speech at an Ankara art gallery.
The killing looked like it was designed to try to hinder the battle against terrorism in Syria, said Lavrov.
"We will take measures at this meeting (in Moscow on Tuesday) that will make it impossible for those who nurtured the people who ordered and organised this crime to realise their plans," said Lavrov.
Lavrov said he had spoken by phone with his Turkish counterpart, Mevlüt Çavuşoğlu, after the ambassador's murder.
Çavuşoğlu arrived in Moscow late on Monday for Tuesday's meeting.
The Russian Foreign Ministry said the two men had agreed the ambassador's killing underlined the need to step up the fight against terrorism.
