Turkish President Recep Tayyip Erdogan narrowly won a controversial referendum on Sunday that will tighten his grip on power, but the knife-edge result left the country bitterly divided and the opposition crying foul.

The country remains deeply divided, with a razor-thin margin separating the two sides in the hotly contested poll to expand powers of President Recep Tayyip Erdogan.

Erdogan claimed victory for the “yes” vote as state media reported that, with nearly all votes counted, 51.4% had voted in favor versus 48.6% against. A total of 47.5 million votes were cast, the Anadolu news agency said.

Voters were asked to endorse an 18-article reform package put forward by the ruling Justice and Development Party that would replace the current system of parliamentary democracy with a powerful executive presidency.

Opponents to the referendum result are expected to take to the streets across the country Monday to protest the result. The Republican People’s Party (CHP) questioned the legitimacy of the results, saying the country’s electoral authority had decided to “change the rules in the middle of the game.”

The High Electoral Board initially said it would not accept ballots that were missing ballot commission stamps, but changed course after voting was underway, saying it would accept unstamped ballots “unless they are proven to have been brought from outside.”

The opposition said this would affect the legitimacy of the vote and called for a partial recount of about 37% of the votes, said Erdal Aksunger of the CHP. He left the door open to challenging a higher percentage of the ballots.

The official results will arrive in about 10 days, after any objections have been considered, Supreme Electoral Council President Sadi Guven said.

Source: Agencies