Erdogan has sought but failed to establish a foothold as a mediator in the Palestinian conflict that has roiled the region since October 7, Barron's reports.
But Erdogan has remained discreet about his meetings with the Hamas head.
"We will keep the agenda between us and Mr. Haniyeh," Erdogan said when questioned by journalists on Friday. Hamas said the war in Gaza would figure in the talks.
Turkish media reported that the meeting at the Dolmabahce palace on the banks of the Bosphorus began shortly after 2:30 pm (1130 GMT).
With Qatar saying it will reassess its role as a mediator between Hamas and Israel, Erdogan sent Foreign Minister Hakan Fidan to Doha on Wednesday in a new sign that he wants a role.
"Even if only I, Tayyip Erdogan, remain, I will continue as long as God gives me my life, to defend the Palestinian struggle and to be the voice of the oppressed Palestinian people," the president said Wednesday when he announced Haniyeh's looming visit.
MNA/PR