Cabs formed blockades at the entrance to motorways as other protesters said they would drive slowly through the capital all day, creating massive jams.

Taxi drivers - some hailing from Britain, Spain and France - blocked the Schuman roundabout outside European Union institutions and lit flares.

Traditional taxi drivers have objected to Uber in markets across the world, accusing it of taking their business unfairly without having to meet the same insurance and licensing costs.

Uber says it already operates a fully licensed service in most EU countries and complies with local regulations.

In Brussels, protesters said they were already losing business to Uber and were angry about a proposed creation of a new licence that they felt would make things even worse by putting ride-hailing drivers on the same level as them.

Currently traditional drivers can sell or pass their licenses on to others with the vehicles, often at a premium that they say is justified by the their additional costs.

The new licence, proposed by Pascal Smet, the Brussels capital region minister for mobility and public works, would be tied to an individual driver, not a vehicle.

Smet argues the move would bring new services like Uber fully into the regulatory framework, ensuring social and fiscal rules apply to them.

"Uber is really hurting us," said taxi driver Alireza Khododad. Smet "wants to set everybody on equal footing even though they (Uber) didn't have to pay for it," he added.

“In reality, we want for Uber to leave ... We have children that need to live, and Uber is taking everything,” said Andraoui Faousi, another Brussels taxi driver.

Joost Verdiesen, General Manager for Uber in Belgium, said in a blog post that the reform of the licensing system was long overdue.

"We agree that a reform is needed to help tackle mobility issues and increase the strong potential for professional drivers to fully contribute to better mobility," Verdiesen wrote.

Uber decided in 2015 to suspend its UberPOP service using amateur drivers in Brussels after a court ordered it shut down and instead uses professional licensed drivers. It did the same in several other European cities.

(Reporting by Natalie Rice; Editing by Andrew Heavens)

By Samantha Koester and Julia Fioretti