Saudi Arabia has announced it was declining its United Nations Security Council seat.
It cited "double standards" that made it hard for the world body to end conflict and wars.
"The kingdom sees that the method and work mechanism and the double standards in the Security Council prevent it from properly shouldering its responsibilities towards world peace," the foreign ministry said in a statement.
It said it was unable to take its seat until reforms were introduced, but did not specify what reforms it wanted.
The Security Council has been divided on how to handle the civil war in Syria, with western powers pushing for stronger sanctions against President Bashar al-Assad and Russia vetoing resolutions to that end.
Saudi Arabia has been backing rebels in that conflict.
The United States, Britain, France, Russia and China are permanent members of the Security Council and hold veto powers.
Other states are brought onto the body on a rotating basis.