Mongolians go to the polls in parliamentary elections on Friday, with the ruling party widely expected to win despite deepening public anger over corruption and the state of the economy.

Voters across the vast, sparsely populated nation of 3.4 million will exercise their democratic rights to elect 126 members of the State Great Khural in a country surrounded by authoritarian powers China and Russia.

Analysts expect the ruling Mongolian People's Party (MPP), led by Prime Minister Luvsannamsrain Oyun-Erdene, to retain the majority it has enjoyed since 2016 and govern the resource-rich country for another four years.

Yet there is deep public frustration over endemic corruption, as well as the high cost of living and lack of opportunities for young people who make up almost two-thirds of the population.

There is also a widespread view that the proceeds of a decade-long boom in coal mining that fuelled double-digit growth are being hoarded by a wealthy elite.

"A few elites benefit from the (mining) sector, not the ordinary people," Tumurkhuyag Bayanmunkh, a 46-year-old retired miner, told AFP.

"Politicians need to stop stealing."

Polls open at 7 am local time (2300 GMT Thursday) and close at 10 pm.

Alcohol sales have been banned in the capital until Saturday while the election unfolds, Ulaanbaatar authorities said.

Preliminary results are expected to come within a few hours despite Mongolia's vast size, thanks to automated vote counting.

The streets of Ulaanbaatar -- home to almost half the population -- have been decked out with colourful campaign posters touting candidates from across the political spectrum, from populist businessmen to nationalists, environmentalists and socialists. 

And, for the first time in almost a decade, parties are required by law to ensure that 30 percent of their candidates are women in a country where politics is dominated by men.

Campaigning wrapped up on Wednesday, with the MPP holding a triumphant rally in the rural town of Zuunmod at which it promised voters "victory for the people".

- Young voters unimpressed -

Younger voters are not convinced and the failure of the main opposition Democratic Party to provide a credible alternative has fuelled the rise of minor parties.

The centre-right anti-corruption HUN party is expected to increase its parliamentary representation through its social-media savvy, professional candidates who enjoy significant support among the urban middle classes.

"I think young people are more aware of the activities of political parties," said Norovbanzad Ganbat, a 24-year-old IT worker.

"They can see what the MPP has done in the last four years," she said. "That's why young people don't vote for this party."

Taking to the stage at Wednesday's rally, Oyun-Erdene blamed his political opponents for turning Mongolia into a "land of corrupt leaders" and called for a return to "discipline".

Mongolia has plummeted in Transparency International's Corruption Perceptions Index under his party's rule.

It has also fallen in press freedom rankings under the MPP and campaigners say there has been a notable decline in the rule of law.

A survey by the Sant Maral Foundation, Mongolia's top independent polling body, suggested more than a third of Mongolians believe the country is "changing into a dictatorship".

"I'll describe this election as a referendum on... Prime Minister Oyun-Erdene and whether he will manage to get a mandate to rewrite Mongolia's social contract," Bayarlkhagva Munkhnaran, political analyst and former adviser on the National Security Council of Mongolia, told AFP.

"This social contract will be about turning Mongolia into a proper electoral autocracy whereas, 10 years ago, Mongolia used to be respected as a liberal democracy," he said.

The MPP is the successor to the communist party that ruled Mongolia with an iron grip for almost 70 years but nonetheless remains popular, particularly among rural, older voters, and commands a sprawling, nationwide campaign apparatus.

"Oyun-Erdene has done a really good job," Sodanjamts Oyunchimeg, the 47-year-old leader of a small administrative area, told AFP at Wednesday's rally. 

"I really support his work."