The group, which controls Gaza, is designated as a terrorist organization in the US, Europe and several other countries.

President Recep Tayyip Erdogan met the leaders in Istanbul on Saturday. The Hamas delegation was lead by the head of its political bureau Ismail Haniyeh, and included deputy chief Saleh Al-Arouri - wanted in the US as a terrorist.

“The United States strongly objects to Turkish President Erdogan hosting two Hamas leaders in Istanbul,” State Department spokeswoman Morgan Ortagus said.