Ankara (AFP) - Turkish Prime Minister Recep Tayyip Erdogan on Friday slammed Egypt's President Abdel Fattah al-Sisi as an illegitimate tyrant, saying Cairo could not be relied upon to negotiate a truce with Israel.

"Is Sisi a party (to a ceasefire)? Sisi is a tyrant himself," Erdogan told reporters.

"He is not different from the others," he said, adding that it was Egypt's current rulers who were blocking humanitarian aid channels to the Gaza Strip ruled by the Islamist Hamas movement.

Egypt's Foreign Minister Sameh Shoukri said Erdogan's comments were "unacceptable".

"They have no link with the events in Gaza and do not help in the protection of the people of Gaza," Shoukri said at a news conference in Cairo with his Italian counterpart Federica Mogherini.

Erdogan should rather push all the concerned parties for a ceasefire in Gaza, said Shoukri.

Relations between Ankara and Cairo have been strained since the Egyptian military ousted last year Islamist president Mohamed Morsi in what Erdogan has repeatedly called a "coup".

The spat came to a head in November when Egypt's military rulers expelled Turkey's ambassador over Erdogan's support for Morsi, prompting a tit-for-tat response from Ankara.

Erdogan, who portrays himself as the global Muslim leader who speaks up for Palestinian rights, said supporting an Egyptian proposal for a ceasefire would mean legitimising the administration in Egypt.

"Egypt is not a party ... They are trying to legitimise (the Sisi administration) in Egypt. It is not a legitimate administration. It is illegitimate," he said, lashing out at Israeli attempts to exclude Hamas.

"Hamas is a party there," he said.