CAIRO — Egypt has accused Turkish President Tayyip Erdogan of supporting terrorists and seeking to provoke mayhem in the Middle East after he questioned the legitimacy of Egyptian President Abdel Fattah al-Sisi in a speech at the UN General Assembly.

Ties between Ankara and Cairo have been strained since then-army chief Sisi toppled elected President Mohamed Morsi of the Muslim Brotherhood last year after mass protests against his rule.

Egyptian security forces then mounted one of the fiercest crackdowns against the Islamist movement, killings hundreds of supporters at a Cairo protest camp, arresting thousands and putting Morsi and other leaders on trial.

After world leaders gathered at the United Nations, Erdogan delivered a speech which featured stinging criticism of Sisi’s rise and what he called inaction after Morsi’s overthrow.

“Again, those objecting (to) the murders in Iraq, Syria and the murder of democracy in Egypt are subjected to certain unfair and groundless accusations and almost immediately accused of supporting terrorism,” said Erdogan.

“The United Nations as well as the democratic countries have done nothing but watch the events, such as overthrowing the elected president in Egypt and the killings of thousands of innocent people who want to defend their choice. And the person who carried out this coup is being legitimized.”

In a statement, Egypt’s foreign ministry dismissed Erdogan’s comments on Sisi.

“There is no doubt that the fabrication of such lies is not something strange that comes from the Turkish president, who is keen to provoke chaos to sow divisions in the Middle East region through its support for groups and terrorist organizations,” the foreign ministry said.

Erdogan’s comments prompted Egyptian Foreign Minister Sameh Shukri to cancel a meeting on the sidelines of the General Assembly with his Turkish counterpart, according to the statement.

Morsi’s Muslim Brotherhood has close ties with Erdogan’s AK Party.