"So far Idleb, Hama and Homs and of course the objective, Damascus: the advance of the opponents continues. We wish this advance to continue without incident," said Erdogan.

Syria, which has a long border with Turkey, has become a new focus of international concern as the armed groupes take a series of cities from Syria's army.

Erdogan was long a supporter of the Syrian opposition after the civil war erupted in 2011 but had tried, with Russian mediation, to reconcile with Assad in recent months.

On the topic of relations with Assad, the Turkish leader claimed there was no answer to his offer of talks.

Assad had previously said he was open to meeting Erdogan but it depended on the encounter's "content", noting Turkey's presence in Syria was a key sticking point.

"I told him 'Come, let's meet to discuss the future of Syria together'. But I never had a positive response from Assad," Erdogan said.

Turkey's Foreign Minister Hakan Fidan will meet counterparts from Russia and Iran in Qatar on Saturday to discuss the Syria civil war, a foreign ministry source said. The meeting will be held on the sidelines of the Doha Forum.

Turkey has a long border with Syria and has become home to about three million Syrian refugees since 2011.

Since 2016, Ankara has launched successive cross-border offensives, mainly to clear the area of the Kurdish-led Syrian Democratic Forces (SDF).

*This story was edited by Ahram Online.