The leader of Turkey’s main nationalist party has declared victory for the referendum to expand the powers of the country’s presidency.

Nationalist Action Party head Devlet Bahceli said in a statement that Turkish voters chose of their free will to move the country from a parliamentary to a presidential system of government.

Bahceli called the outcome “a very important success; a win that makes neglect and denial impossible.”

He says Turkey rejected international “pressure, blackmail, imposition, force and threats by the whole world to put the ‘no’ choice forward.”

The party, the fourth largest in parliament, backed Turkey’s President Recep Tayyip Erdogan and the governing Justice and Development Party in their push to change Turkey’s parliamentary system into a presidential one.