Turkish President Tayyip Erdogan on Wednesday called Syrian President Bashar Al Assad a terrorist and said it was impossible for Syrian peace efforts to continue with him.

Syria's foreign ministry quickly responded by accusing Erdogan of himself supporting terrorist groups fighting Assad in Syria's civil war.

Turkey has demanded the removal of Assad from power and backed rebels fighting to overthrow him, but it has toned down its demands since it started working with Assad's allies Russia and Iran for a political resolution.

"Assad is definitely a terrorist who has carried out state terrorism," Erdogan told a televised news conference with his Tunisian counterpart Beji Caid Essebsi in Tunis.