Citizens of Turkmenistan are going to the polls on Sunday for a presidential vote expected to further tighten the incumbent leader's hold over the gas-rich Central Asian country.

Gurbanguly Berdymukhamedov, 59, faces eight other candidates including subordinate regional officials, the director of a government-owned oil refinery and a representative of the country's state agribusiness complex.

But these other men are completely loyal to Berdymukhamedov, who rose to power suddenly following the death of predecessor Saparmurat Niyazov in 2006.

"The opposition candidates are fairly irrelevant to the extent that people have been recruited from within the regime or the government departments, they are just a facade to show that the recoronation of the president ends up successfully," Luca Ancheski, a specialist on Turkmenistan at the University of Glasgow, told Al Jazeera.

Voting in the country of over five million people began at 7:00am (02:00 GMT) and will continue until polling stations close at 7:00pm (14:00 GMT), the central electoral commission confirmed.

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Berdymukhamedov, a dentist by training, has kept in place Niyazov's repressive political system which tolerates no political opposition or public expressions of discontent.

"There is no position or opinion of [Turkmen] on the elections, when there is no media which makes the assessment of what people really think," Ancheski said.

Al Jazeera's Central Asia expert, Mutiullah Tayeb, said the latest report by Reporters Without Borders mentions the crackdowns on some independent journalists in the country.

"In the absence of a powerful opposition, and the crackdown on press freedom, I don't see any real changes in the near future," Tayeb said.

In the previous election in 2012, Berdymukhamedov won 97 percent of the vote.

Last year, Turkmenistan amended its constitution in a way that could allow Berdymukhamedov to stay in power indefinitely, removing the 70-year age limit for presidential candidates and extending the presidential term to seven years from five.

"Despite some superficial changes in the democratic decor by allowing some unknown competitors in the election race, a real change is far away. Turkmenistan will remain one of most authoritarian states so far," Tayeb told Al Jazeera.

This consolidation of power has been taking place against a background of slowing economic growth and shortages of foreign currency due to Russia's decision to halt imports of Turkmen natural gas, Ashgabat's main source of export revenue.

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Moscow had long been the main buyer of Turkmen gas and sales to China, although significant, have not completely offset the loss of Russian money flows.

Faced with budget deficits after years of surpluses, the authorities are considering scaling down a generous welfare system which includes free petrol rations.

Amid the gas fight, Turkmenistan has also flatly rejected the idea of Russia providing military assistance to the Central Asian nations in the light of escalating violence in neighbouring Afghanistan; it has also vehemently denied claims of violent incidents at the Afghan border.