Turkish President Recep Tayyip Erdogan has claimed that former Egyptian President Mohammed Morsi didn't die of natural causes, but that he was killed.

During a speech in Istanbul, Erdogan cited as evidence that the deposed Egyptian president allegedly "flailed" in a Cairo courtroom for 20 minutes Monday and nobody assisted him.

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The Turkish leader said Wednesday: "Unfortunately, Mohammed Morsi was on the ground of the courtroom flailing for 20 minutes. No official there intervened. Morsi did not (die) naturally, he was killed."

Erdogan said Turkey would do everything in its power to ensure Egypt faces trial in Morsi's death. He also called on the Islamic Cooperation Organization to "take the necessary action" over Morsi's death.