Muizzu, 45, helms a party that presided over an influx of Chinese loans when it last held power in the atoll nation, better known for its luxury beach resorts and celebrity tourists.

He won 54.06 percent of the vote in the run-off contest, prompting incumbent Ibrahim Mohamed Solih to concede defeat shortly before midnight.

"Congratulations to president-elect Muizzu," Solih wrote on X, formerly Twitter. "I also congratulate the people who have shown a peaceful and democratic process."

Muizzu made a brief appearance outside his party's campaign headquarters to urge supporters not to celebrate until Sunday morning, when campaign restrictions officially come to an end.

Solih, 61, will serve as caretaker president until his successor is inaugurated on November 17.

The result upends Solih's efforts to revert the country's diplomatic posture back towards New Delhi since taking office five years ago.

Muizzu played a pivotal role in an earlier government's development programme, bankrolled in part by financial largesse from China's Belt and Road infrastructure initiative.

He told a meeting with Chinese Communist Party officials last year that his party's return to office would "script a further chapter of strong ties between our two countries".

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The Maldives sits in a strategically vital position in the middle of the Indian Ocean, astride one of the world's busiest east-west shipping lanes.

Muizzu's mentor, former president Abdulla Yameen, borrowed heavily from China for construction projects and spurned India.

Solih was elected in 2018 on the back of discontent with Yameen's increasingly autocratic rule, accusing him of pushing the country into a Chinese debt trap.

Yameen's turn towards Beijing had also alarmed New Delhi, which shares concerns with the United States and its allies about China's growing assertiveness in the Indian Ocean.

India is a member of the strategic Quad alliance alongside the United States, Australia and Japan.

But Solih's restoration of the Maldives' traditional posture itself proved controversial, with many in the archipelago disapproving of India's outsized political and economic clout.

Muizzu has vowed to free Yameen, currently serving an 11-year sentence for corruption on the same prison island where he had jailed many of his political opponents during his tenure.

In his brief appearance Saturday, Muizzu urged the outgoing president to use his executive power and transfer Yameen to house arrest.

Turnout in Saturday's poll was 85 percent, slightly higher than the first-round vote held earlier this month.

Watchdog group Transparency Maldives said there had been some incidents of "electoral violence," without specifying further details.

Officials said one voter broke open a plastic ballot box, but the ballots were saved and there was no interruption to the count.

Police reported arresting 14 people, mostly for taking photographs of their marked ballot papers and sharing them on social media.