DUSHANBE - Polls closed in ex-Soviet Tajikistan Sunday in a referendum on constitutional changes almost certain to strengthen the hold of long-time President Emomali Rakhmon and his family over the impoverished Central Asian state.

The country's electoral commission, which declared the vote valid, said some 88.3 percent of the roughly 4.3 million eligible voters had cast ballots by 1300 GMT. Polls closed at 1500 GMT.

The 63-year-old autocrat has ruled Tajikistan for nearly a quarter of a century, demonstrating what critics say is an increased disregard for religious freedoms, civil society and political pluralism in recent years.

Many residents of the near million-strong Tajik capital appeared enthusiastic in their support for Rakhmon, who led the country out of a five-year civil war that began in 1992, less than a year after independence.

"Rakhmon brought us peace, he ended the war, and he should rule the country for as long as he has the strength to," 53-year-old voter Nazir Saidzoda told AFP.

Other voters were more pessimistic about their leader's ability to pull the country of eight million out of economic difficulty and curb the rise of extremism in the volatile region.

"Everything that is being done is for (the regime) to hold onto power for as long as possible," said 37-year-old Marifat Rakhimi. "We are waiting for a better economy and the disappearance of corruption."

The term limit amendment applies only to Rakhmon, owing to the "Leader of the Nation" status parliament voted to grant him last year, which also affords him and his family permanent immunity from criminal prosecution.

Other amendments include lowering the minimum age required to be elected president from 35 to 30 and a ban on the formation of parties based on religion.

The age limit change could position Rakhmon's 28-year-old son, Rustam, for an early succession, while restrictions on political parties come amid the ongoing trial of key members of a banned Islamic party.

The Islamic Renaissance Party of Tajikistan (IRPT) had been widely viewed as moderate before the government branded it a terrorist group last year, stripping away the most significant formal opposition to the Rakhmon regime.

In the months leading up to the referendum, authorities have pushed through a number of initiatives glorifying Rakhmon's rule, which is regularly lambasted by rights organisations as corrupt and repressive.

Earlier this month, the autocrat signed off on a law creating a holiday in his honour proposed by parliamentarians in the two-chamber legislature completely loyal to his administration.

In February the republic's youth affairs committee launched a contest for the best essays by schoolchildren in praise of the strongman's "heroic" rule.

State television reported 90 percent of the population of Rakhmonobod -- a village in eastern Tajikistan named after Rakhmon earlier this year -- had cast votes Sunday within three hours of polls opening.

Media watchdog Reporters Without Borders (RSF) said in a statement Saturday that the Tajik government had been "blocking", "intimidating" and "threatening" independent media outlets in the build-up to the referendum.

"Depriving the population of freely reported news and information before such a crucial political event constitutes an all-out denial of democracy," Johann Bihr, the head of RSF's Eastern Europe and Central Asia desk, was quoted as saying in the statement.

The CEC is expected to announce the result of the referendum on Monday morning.