Rival political camps in Macedonia staged a third day of protests Tuesday as the embattled prime minister and the opposition leader prepared to hold talks to try to end the crisis.

About 150 opposition supporters rallied outside the main government building in Skopje to press their demands that Prime Minister Nikola Gruevski step down.

Just two kilometres (1.5 miles) away, about 50 supporters of the conservative leader spent the night in a tent camp outside parliament in a show of solidarity with Gruevski.

He and opposition leader Zoran Zaev were to meet in Strasbourg later Tuesday in a bid to find a solution to the crisis under the auspices of European Parliament.

Under pressure from the European Union, which Macedonia has applied to join, leaders of the country's four main political parties met on Monday, but the talks only lasted 90 minutes and did not even begin to tackle the crisis.

The rival camps have rallied tens of thousands of supporters in demonstrations over the past two days, highlighting the deep divisions that plague the tiny former Yugoslav republic.

The centre-left opposition -- which drew more than 20,000 people to a protest rally on Sunday -- accuses Gruevski of corruption, wiretapping and other wrongdoings, and has vowed to remain on the streets until he quits.

"People here came of their own free will, while those who took part in Gruevski's rally were employees paid by the state who were obliged to gather," said Bojanco Micevski, an unemployed chemistry professor from the northeastern town of Kriva Palanka.

On Monday, 30,000 people attended a rival rally to support the 44-year-old Gruevski, who has been in power in the southeastern European country for nine years.

The pro-government camp insists that Gruevski should continue to rule in accordance with the results of an April 2014 election, which have been contested by the opposition ever since.

"We clearly said yesterday evening that results of the elections should be respected, we want simply to show our support to the government," Predrag Petrovic from the northern town of Kumanovo told AFP as he spent night in the camp set up in a park across from the parliament building.

Macedonia has been dogged by political crisis since the disputed elections and was also left reeling after a clash between police and ethnic Albanian gunmen left 18 people dead earlier this month.

Ethnic Albanians make up about one quarter of Macedonia's 2.1 million population.