The Venezuelan opposition won the European Parliament's prestigious Sakharov human rights prize on Thursday, sources told AFP, a boost for the movement opposing socialist President Nicolas Maduro.

The prize was awarded to the Venezuelan National Assembly, dominated by opposition parties, and to political prisoners, several parliamentary sources told AFP ahead of the official announcement.

The award comes after months of anti-Maduro protests in Venezuela left 125 people dead and as the oil-rich country teeters on the brink of economic collapse, with the population struggling with shortages of food and such basic necessities as toilet paper and soap.

Belgian liberal MEP Guy Verhofstadt, whose parliamentary group put the Venezuelans up for the award, urged international powers to "join us in the fight for freedom" for the country's people.

"This award supports the fight of democratic forces in favour of a democratic Venezuela and against the Maduro regime," he said on Facebook.

The award comes as the coalition against Maduro appears close to disintegration, with the departure of a key leader on Tuesday bolstering the president ahead of elections next year.

The opposition also suffered a heavy defeat in October 15 regional elections by Maduro's socialists who swept the vote in 18 of Venezuela's 23 states, though the Organization of American States declared the elections illegitimate.

Named after the dissident Soviet scientist Andrei Sakharov, who died in 1989, the prize is awarded every year to honour individuals who combat intolerance, fanaticism and oppression, often falling foul of their governments as a result.

The prize worth 50,000 euros will be handed to the winner during an official ceremony in the European Parliament on December 13.

Last year's prize was awarded to Nadia Murad and Lamia Haji Bashar, two Yazidi women activists who escaped the Islamic State group in Iraq