Tens of thousands of Serbs marched in Belgrade for the third consecutive Saturday against what they contend is the increasingly autocratic rule of Serbia’s President Aleksandar Vucic.

Protesters carried signs saying “It [the resistance] has begun!” Some wore yellow vests, a nod to the gilets jaunes worn by protesters in France, that read “one in five million.” This was a reference to Mr Vucic’s comment about last week’s protests that “even if there were five million people in the street,” he would not cede to the opposition’s demands for electoral reform and increased media freedom. Serbia’s population is 7m.

The demonstrations have brought together a rainbow coalition of far-right radicals and dedicated leftists, as in Hungary. The groups allege that Mr Vucic has all but consolidated control over the courts, media and security services, and announced before the protest that they would boycott future elections until their conditions for a fair vote were met.

“The fear from the regime’s oppression has started to melt away,” Vuk Jeremic, who leads the small opposition People’s Party told the FT by phone from the protest. “From here, there will be no reversing — the genie of freedom has left the bottle.”

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The protesters marched to the headquarters of Serbia’s public broadcaster RTS, calling for the channel to “allow the opposition to express its views and thus allow the voice of other [non-governmental] political options,” as the alliance wrote in a press release.

Organisers estimated that Saturday’s protest was the largest one yet, with between 35-40,000 people in the streets. Rallies were sparked three weeks ago after politician Borko Stefanovic was beaten unconscious by thugs with brass knuckles at an opposition rally in the central Serbian city of Krusevac. The Alliance for Serbia, an opposition umbrella group, blamed the violence on the “dirtiest witch-hunt which Aleksandar Vucic’s regime wages daily against political opponents”. The next day, thousands took to the streets with the slogan “no more bloody shirts!”

Mr Vucic has publicly condemned the attack on Mr Stefanovic and denied the accusations levelled against him by his political foes.

“You can only win the election, and when you do, go ahead and fulfil what was promised to the people, but I will not be pressed to do anything, and that is what sets me apart from others,” Mr Vucic said after last week’s protest.

Mr Vucic is a reformed extreme nationalist who served as minister of information under Slobodan Milosevic but now hopes to bring Serbia into the EU. He has been in power since 2012, serving as premier before his election as president in April 2017. Fury over his victory in the first round against 10 competitors brought tens of thousands of people to the streets for two months before fizzling out. The Organisation for Security and Co-Operation in Europe found that “biased media coverage, an undue advantage of incumbency and a blurred distinction between campaign and official activities undermined the level playing field for contestants”.

Yet, as in neighbouring Hungary, the opposition has been extremely fragmented and few credible challengers have emerged: in the 2017 presidential elections, a joke candidate came in third place with 9 per cent of the vote.

Western diplomats see Belgrade and Mr Vucic as the linchpin to stability in the western Balkans, with hopes that Serbia will reach a deal with its former province Kosovo and that Mr Vucic can temper Milorad Dodik, the irredentist Serb member of Bosnia and Herzegovina’s tripartite presidency.

The EU said in a recent report that improving “the situation regarding freedom of expression and freedom of the media” is a prerequisite for joining the bloc and the European Commission said that the funding model for the two public broadcasters “leaves them vulnerable to political influence”.

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