Former Maldivian President Mohamed Nasheed has won a bitterly-contested presidential elections, but has failed to secure an outright majority to avoid a run-off, official results showed.

Nasheed received 45.08 percent of the popular vote and is set for a run-off with Abdulla Yameen, the half brother of former autocrat, Maumoon Abdul Gayoom, who garnered 31.21 percent of the vote.

Nasheed he was still short of the 50 percent needed to win outright to avoid a runoff intitially scheduled for Sunday but postponed until next Saturday.

In a late development Saturday, a member of candidate Qasim Ibrahim's Jumhoory Party filed a lawsuit asking the Supreme Court to delay the runoff, citing the inability to campaign for a second round.

The Commonwealth's 53-member special envoy to the Maldives, Don McKinnon, said Saturday's presidential ballot was a "good election" even though it failed to deliver an outright winner and triggered a second round.

"It is important now that the electoral process move forward swiftly to its conclusion, with the holding of the second round," he said as the second placed Abdulla Yameen insisted he needed more time to face Saturday's winner Mohamed Nasheed at a runoff.

"It is unreasonable and unacceptable for parties to continue to demand changes to an agreed election date," McKinnon said.

This was the country's third bid in two months to choose a new president and end a political crisis sparked by the toppling of their first freely-elected leader nearly two years ago.

Low voter turnout

Voter turnout on Saturday appeared to be less than a previous vote in September, the result of which was annulled by the Supreme Court. About 240,000 people were eligible to vote.

The Indian Ocean archipelago, a popular tourist destination, has been the focus of intense diplomatic pressure since last the results of last polls cancelled.

A previous round of elections scheduled for October 19 was scuttled by police saying that the same two candidates, Yameen and Ibrahim, had not approved the electoral roll and therefore the ballot could not go ahead.

Western and Asian diplomats monitoring Saturday's vote said it had gone off well without any incidents.

Saturday's vote appeared to be a repeat of the September 7 vote which was rescinded by the court following allegations that flawed voter lists had been used, although international observers had given it a clean chit.

In that election, Nasheed had secured 45 percent of the vote, but not enough to win in the first round. Yameen had 25 percent and Ibrahim 24 percent.

Outgoing President Mohamed Waheed, who is not contesting, got five percent of the vote in September.