Mongolians voted on Friday in the country's first ever presidential runoff after the first round of elections failed to produce a clear winner following campaigns tainted by corruption allegations.

The presidential race went into a runoff after none of the three candidates won a majority in last month's election in the resource-rich country.

A populist former martial arts star, Khaltmaa Battulga of the opposition Democratic Party, won the most votes but fell short of the required majority.

Voters regard Battulga as a resource nationalist who is suspicious of southern neighbour China.

He faces the candidate of the ruling Mongolian People's Party (MPP), Miyeegombo Enkhbold, who came second.

Enkhbold has stood behind the current government, pledging to stay the course for economic recovery following a $5.5bn rescue package from the International Monetary Fund and partners in May.

Battulga has captured the attention of voters who feel Mongolia has got a bad deal on investments, promising greater government control of strategic mines, such as Rio Tinto's, Oyu Tolgoi copper mine.

Enkhbold, for his part, has promised to deliver money owed from a universal child welfare fund.

"Even thought they make promises, they won't do anything," Dagvadorj Gandi, 23, a voter in the capital Ulaanbaatar told Reuters news agency. "Honestly, there's nobody to choose from," Gandi added.

Rentsen Ichinkhorloo, a 49-year-old engineer, said he thought elected officials were just putting themselves ahead of the country's interests: "They make their promises to get people's votes, but afterwards won't keep them."

Results are expected some time on Saturday.

'White Ballot'

The race has been clouded by allegations of corruption and voter fraud by all sides, with many voters dismayed by their choice of candidates and the government's inability to bring them prosperity.

But the country's 1.9 million voters also have a third option, according to the so-called "White Ballot" campaign - to leave their votes blank.

"Our goal is to have every voter know they have an option to vote for none of the above," Mogi Badral Bantoi, spokesman for the campaign, said.

For many voters, handing in blank ballots is a last-ditch effort to deny either candidate a majority, so forcing a re-run of the poll from scratch, with selection of fresh candidates.