The Maldives, home to 400,000 people and best known as a tropical paradise for tourists, has experienced political unrest since Mohamed Nasheed, its first democratically elected leader, was forced to quit amid a mutiny by police in 2012.
Nasheed, the sole candidate in last week's primary election held by his Maldivian Democratic Party (MDP), was convicted of terrorism charges in 2015 and sentenced to 13 years in prison after a controversial and widely criticised trial.
Maldives police executing a court order last week disrupted the MDP's effort to pick Nasheed as its candidate for the election.
Elections Commission chief Ahmed Shareef said the 2018 presidential poll will be held on Sept. 23 in "the most transparent and open" manner.
Shareef said observers from eight countries and the EU and the Organisation of Islamic Cooperation (OIC) would be invited.
"Unlike previous elections this election will be fully trusted by the people. We will not be withholding any information other than what we have to keep secret lawfully," he told reporters in Male.
The election will be held amid widespread criticism of civil and political rights abuses by President Abdulla Yameen's government, with opposition leaders either in exile or behind bars, and a crackdown on media and activists.
The opposition has accused the government of locking up most of its leaders who could challenge Yameen's bid to be re-elected for his second five-year term, a charge the government denies.
Yameen's administration has rejected a demand by a U.N. human rights watchdog to let Nasheed stand for the presidential election.
In a tweet, Nasheed said: "MDP primaries proved EC has zero credibility. EC must change to have a genuinely free, fair and inclusive election".
The Elections Commission has declared last week's MDP referendum unlawful over Nasheed's ineligibility to run for office after being found guilty of ordering the abduction of a judge in March 2015.
While President Yameen is seeking re-election for a second term, the opposition has held talks to field a common candidate.
The Indian Ocean island chain has faced upheavals since February, when Yameen imposed a 45-day state of emergency to annul a Supreme Court ruling that quashed the convictions of nine opposition leaders, including Nasheed.
During the emergency, Yameen's administration arrested former president Maumoon Abdul Gayoom, the chief justice, another Supreme Court judge and a Supreme Court administrator on charges of trying to overthrow the government.
In 2016, Nasheed was allowed to go on medical leave to Britain, where he received political asylum. Since last year, he has been in Sri Lanka, working to unite opposition parties to defeat Yameen.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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