MALE (Reuters) - The Supreme Court of the Maldives on Sunday upheld the results of last month’s presidential election in an unanimous judgment after President Abdulla Yameen challenged his own defeat in the poll.

FILE PHOTO: Maldives President Abdulla Yameen attends a signing meeting at the Great Hall of the People in Beijing, China December 7, 2017. Fred Dufour/Pool via REUTERS/File Photo

Supporters of Yameen, who initially conceded defeat to joint opposition leader Ibrahim Mohamed Solih, said the vote had been rigged and that some of the ballot papers were fraudulent.

The judgment said that Yameen had not been able to prove that electoral fraud had taken place, and that any issues with the voting process would not have affected the result given the margin of Solih’s victory.

Yameen, a hardliner who jailed many of his political opponents including his own half brother during his presidency, filed the petition in the Supreme Court on Oct. 10.

The official count of the Sept. 23 poll showed joint opposition leader Ibrahim Mohamed Solih had won a surprise victory by a margin of 16.8 percent.

“The court rules that there is no legal or constitutional basis to question the legality of the election based on the evidence submitted to this court,” said Chief Justice Dr. Ahmed Abdulla Didi, on behalf of the five justices hearing the petition.

Hundreds of protestors outside the Supreme Court called for the arrest of Yameen after the verdict. Unlike previous hearings in the case, ruling party supporters did not gather outside the court.

The Maldives Elections Commission had said the September vote had been free and fair, with a turnout of 89.2 percent.

The United States, which has previously warned of sanctions if the country did not hold free elections, was quick to welcome the verdict.

“We welcome the Maldives Supreme Court decision and look forward to working with President Solih after his inauguration,” said Robert Hilton, the acting head of the U.S. Embassy in Sri Lanka in a tweet. “It’s a new and positive era for all Maldivians.”

Opposition members had previously expressed concern about a smooth transition of power, due on Nov. 17.

Since the petition was filed, four members of the Maldives Elections Commission have fled the country citing intimidation and threats.

However, Yameen said last week he was preparing to step down despite challenging the election result.

The tourist paradise has been in political upheaval since February, when a state of emergency was imposed by Yameen to annul a court ruling that quashed the convictions of nine opposition leaders, including former president Mohamed Nasheed.

The Maldives, located near key shipping lanes in the Indian Ocean, has become a battleground for China and India as they compete for influence in the region.

Pro-Beijing Yameen drew the islands closer to China, and the country is developing the Maldives’ infrastructure as part of its Belt and Road Initiative to boost trade and transport links across Asia.