BELGRADE (AFP) - Serbia's ruling centre-right Serbian Progressive Party (SNS) party was set for a landslide victory in snap polls on Sunday, according to observer estimates, cementing its grip on power after pledging tough economic reforms and a route into the European Union (EU).

The SNS won around 50 per cent of the vote, giving it a majority in the 250-seat parliament, independent electoral monitors Cesid said.

If confirmed in final results, it would be the highest score in Serbia's parliamentary elections since 1990, after the fall of communism, and would also allow the party to form a government on its own.

SNS official Nebojsa Stefanovic said his party had won 49.3 per cent of the vote.

The SNS and its leader Aleksandar Vucic - now set to become the next premier - had called early polls in order to win a new mandate to push ahead with economic reforms.

"I want Serbia to pursue a fierce battle against corruption, develop its economy, increase the number of jobs, and for this we need difficult and painful reforms," said Mr Vucic, an ultra-nationalist hawk turned pro-European.

"It will not be easy at all. Thousands of other problems must also be solved," he said after casting his ballot.

The outgoing SNS-dominated cabinet, led by Socialist Prime Minister Ivica Dacic, won support from Brussels to begin EU membership talks only after a historic accord with the breakaway region of Kosovo last year.

Though the SNS won the most votes in the last election in 2012, it gave the post of premier to the Socialist party as part of a coalition deal.

The SNS owes its popularity largely to Mr Vucic's high-profile anti-graft drive that led to the arrest of several tycoons and former ministers.

Serbia - the largest country to emerge after the break-up of Yugoslavia with a population of 7.2 million - has often been seen as a defiant international pariah since playing a central role in the Balkan wars of the 1990s.

But with a fifth of the workforce unemployed and the average monthly salary at just 350 euros ($615), Serbia's leading parties now see membership of the 28-member EU as the only hope for the future.

Although Serbia still refuses to recognise Kosovo's 2008 declaration of independence, it forged a compromise deal last year, in which it agreed to recognise the authority of the government in Pristina over the territory of Kosovo - an agreement that opened the door to accession talks with Brussels.

'NO CHANGE'

Many Serbs, such as 45-year old textile worker Jadranka Milosavljevic, moonlight in the so-called grey economy, with no health or social benefits.

"Ordinary people will see no change. Look at me, it's Sunday, and I'm on my way to my second job to try to make some money for my family," she said.

The next government will have to focus on reforming antiquated labour laws and cutting down on bureaucracy, analysts say.

Serbia's eight billion euro budget is struggling to cope with 1.7 million pensioners and a bloated public sector that employs more than 700,000.

The new government will also have to push through a stringent austerity package, including the privatisation of more than 170 state-owned companies, along with subsidy cuts and tax increases.

But 64-year-old pensioner Borivoje Mikic said he expected no change.

"The barn is the same, only the animals in it change," Mr Mikic said.

Despite the gloomy economy, opinion polls ahead of the election showed a dominant position for the SNS, with 44 per cent voter support.

Unemployed bank clerk Olga Petrovic, 52, said Mr Vucic and his party offered "the first glimmer of hope".

"I know we will have to survive painful times, but at least I see a light at the end of a tunnel."

Analysts expected a final turnout of around 50 per cent, with many voters put off by the seemingly certain SNS victory.

The Socialists were ranked second in opinion polls with 14 per cent, ahead of the opposition Democratic Party with 11 per cent.

Preliminary results are expected early on Monday, with final results by March 20.