VIENNA: Opinion polls indicate that Austrians will decide Sunday in a referendum to remain one of the very few countries in Europe with compulsory military service.

But with turnout expected to be low, the outcome is uncertain and months of lively debate have divided not only voters but also the coalition government ahead of elections due in September.

This will be modern Austria's first ever nationwide referendum, and although not binding, the government has vowed to respect the result.

With the end of the Cold War two decades ago removing the need for large armies, many countries in Europe have done away with the draft, including France in 1996 and Germany in 2011.

In Austria though, some fear that moving to a professional military will push the country to join NATO, endangering the Alpine nation's cherished neutrality.

Interior Minister Johanna Mikl-Leitner said on Saturday that the current system "fits Austria like a glove and is the best guarantee for all future challenges."

At present around 22,000 men over 18 are drafted into six months of military service every year in eight-million-strong European Union member Austria.

Supporters of the status quo say that if conscription goes, it will be tough to attract enough volunteers to keep the size of the army at 55,000 troops.

They also say creating a professional army will be expensive, just as the eurozone member is trying to cut spending.

But the defence minister, Norbert Darabos of the Social Democrats, says that the draft is outdated in an era of "counter-terrorism, cybercrime... (and) failed states".

The army's chief of staff, General Edmund Entacher, has warned however that a professional army would lead "irreversibly to a drop in quality, numbers and ability".

Already Austria spends just two billion euros ($2.7 billion) per year on its military, or 0.6 percent of gross domestic product, one of the lowest in the EU.

Generals have already had to cope with swingeing cuts, forcing them to sell or scrap for example two thirds of the army's tanks.

Others argue a reduced force will be less able to help in disaster relief or participate in international peacekeeping missions abroad as it does now in hotspots such as Kosovo and Lebanon.

Another argument in favour of keeping the draft is that at present, 14,000 young men opt out each year and work instead for nine months helping disabled people and the elderly or working in hospitals.

They thus provide a valuable source of manpower that would be missed if conscription is scrapped, some say.

The referendum has split the government down the middle, with the People's Party backing military service, supported by the far-right Freedom Party.

The People's Party's coalition partners, the Social Democrats of Chancellor Werner Faymann, want a professional force, as do the Greens.

Peter Ulram, political expert at Ecoquest, said that even if voters decide to ditch the draft, the government will find it hard to put this into effect.

"The government will need a large enough majority to change the constitution. This it doesn't have," Ulram said.

The latest opinion polls predict that voters will prefer to maintain conscription by about a 10-point margin, although many were still undecided -- or don't care.

"The parties' tedious squabbling over the army seems to have left a considerable number of Austrians confused and disinterested," the Spectra polling institute said.

Some 6.3 million Austrians are eligible to vote, with the first projections expected soon after polls close at 5:00 pm (1600 GMT) and preliminary results between 6:45-7:45 pm (1745-1845 GMT).