ANKARA • Turkish President Recep Tayyip Erdogan has angrily rejected criticism by international monitors of the referendum result that has granted him extra powers but is disputed by the opposition and has exposed bitter divisions in the country.

He has told thousands of cheering supporters that international observers who criticised the poll should "know your place".

Mr Erdogan yesterday hailed the vote as a major and much-needed step in restoring stability, saying it was the first time that Turkey had changed its political system through "civil politics".

He also said Turkey could hold further referendums on its bid to join the European Union and on reintroducing the death penalty.

United States President Donald Trump called Mr Erdogan on Monday to congratulate him on his victory. The White House said the two leaders also discussed Syria and the fight against the Islamic State in Iraq and Syria.

EU leaders gave more reserved responses. German Foreign Minister Sigmar Gabriel said that bringing back the death penalty would be "synonymous with the end of the European dream".

The "Yes" camp won 51.41 per cent in Sunday's referendum, according to complete results released by the election authorities.

But the opposition immediately cried foul, claiming a clean vote would have made a difference of several percentage points.

The main opposition Republican People's Party and the pro-Kurdish Peoples' Democratic Party said they would challenge the results from most ballot boxes due to alleged violations.

International observers agreed the campaign was conducted on an "unlevel playing field" and that the vote count itself was marred by procedural changes that removed key safeguards.

"The legal framework... remained inadequate for the holding of a genuinely democratic referendum," the OSCE Office for Democratic Institutions and Human Rights and the Parliamentary Assembly of the Council of Europe monitors said in a statement.

Turkey's new political system is due to come into effect after elections in November 2019. It would dispense with the prime minister's post and centralise the executive bureaucracy under the president.

Whatever the outcome of the appeals, the referendum reflected a country sharply divided, with voters in the major cities tending to oppose the changes while those in rural areas, who usually are more religious and conservative, voting in favour of them.

AGENCE FRANCE-PRESSE, NYTIMES