Story highlights Erdogan slammed the Security Council over the Syria war

He called for a no-fly zone in the war-torn country

(CNN) Turkish President Recep Tayyip Erdogan called for an overhaul of the United Nations on Monday, saying its Security Council had failed to address the Syria conflict and other global challenges.

Erdogan gave an unabashed speech in Istanbul at the closing of a NATO meeting, where he slammed the Security Council's concentration of power, reiterating that "the world is bigger than five."

Some humanitarian groups say around 400,000 people have been killed in the Syria war.

"There are so many countries. There are five permanent members of the Security Council and one of those five permanent members can make a decision that binds the rest of the world. That is not fair, that is not just."

"There have been numerous positive steps taken, however, the United Nations failed to act effectively facing a number of issues, Syria included," Erdogan said.

The Security Council, responsible for international peace and security issues, includes five permanent member states -- the United States, China, France, Russia and the United Kingdom -- which all hold the power to veto decisions or resolutions.

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