Ismail Haniyeh, the leader of the militant Palestinian group Hamas in Gaza, arrived in Turkey on Sunday where he went straight into talks with Prime Minister Recep Tayyip Erdogan, dpa reported.
The talks were due to focus on the power-sharing agreement between Hamas and the rival Fatah party, whose leader, Mahmoud Abbas, is the internationally recognised head of the Palestinian Authority, Turkish media reported.
Upon his arrival at Istanbul airport, Haniyeh was driven directly to Prime Minister Erdogan's residence.
Turkey, which recognizes Palestine as an independent state, has been trying to mediate between Hamas and Fatah, whose armed factions have often fought each other in the streets of Gaza.
Last year the two parties agreed to share power pending elections, but the agreement has not been fully implemented.