Ankara and Moscow now "understand each other better than ever before" on the issue, Yildirim said in an exclusive interview with the Russian news agency, Ria Novosti.
He said it is important to concentrate on finding a solution and overcoming the crisis.
Regarding Turkey's mediation between Russia and the Syrian opposition, the premier said Ankara has made a serious contribution and intends to continue its efforts to end the bloodshed in Syria.
"But the regime representatives are not honest on this issue," he said, "it would be useful for Russia to be more effective against the regime, but we are continuing our common efforts,” he said.
"We need to enable the cease-fire and extend help to the harmed people," he added.
Syria has remained locked in a vicious civil war since early 2011, when the Bashar al-Assad regime cracked down on pro-democracy protests with unexpected ferocity. Hundreds of thousands of victims have been since killed and millions displaced.