Serbia’s capital Belgrade is on edge ahead of a major rally against President Aleksandar Vucic’s populist government this weekend, as authorities ramp up efforts to dissuade people from attending.

The protest on Saturday is seen as a culmination of months of anti-corruption demonstrations in the Balkan country and a test for Mr Vucic’s right-wing government, which has faced mounting popular discontent.

The autocratic Serbian leader has repeatedly warned that violence is planned at the rally while also threatening arrests over any incidents.

Tractors were parked by supporters of the Serbian president Aleksandar Vucic in Belgrade (AP)

Mr Vucic’s supporters have been camping in the city centre, fuelling fears of clashes with the protesters.

Despite mounting tensions, tens of thousands of students and other protesters are expected to converge on Belgrade from all over Serbia.

Students who have been marching or cycling toward Belgrade for days are expected to arrive on Friday evening for a festival-like welcome in the city.

Previous student-led rallies in other Serbian cities have been peaceful while drawing huge crowds.

On Friday, tractors were parked around a park outside the Serbian presidency building in Belgrade where Mr Vucic’s supporters, including former paramilitary fighters, have organised a counter-protest.

Authorities said the Parliament building across the street will be locked for the next three days for security reasons.

Authorities are trying to dissuade people from attending the demo (AP)

Also on Friday, Serbia’s railway company Srbijavoz said it was stopping all intercity travel over an alleged bomb scare, a move seen as a way to prevent people from traveling to Belgrade.

University students in Serbia are a key force behind the nationwide anti-corruption movement which started after a concrete canopy collapsed at a train station in Serbia’s north more than four months ago, killing 15 people.

Almost daily protests have rattled Mr Vucic’s firm grip on power in Serbia with the momentum gradually building in favour of the demands for change.

Serbia is formally seeking European Union entry but the ruling populists have been accused of stifling democratic freedoms while strengthening relations with Russia and China.

Major protests are expected this weekend (AP)

Mr Vucic has rejected proposals to form a transitional government that would schedule an election in six months. He has said he will step down “only if they kill me”.

The Serbian President has described the protests as a Western-orchestrated ploy to oust him from power and “destroy” Serbia. He is set to address the nation later on Friday.

Many in Serbia blamed the crash on November 1 in Novi Sad on government corruption and negligence that resulted in poor renovation work on the central train station building.