The Uber app is seen on a smartphone as cabs wait for clients near the Sagrada Familia in Barcelona, on December 9, 2014

Web-based taxi company Uber risks being banned in the Belgian capital Brussels in just the latest legal challenge to its services.

Belgian authorities will back a local taxi firm which alleges unfair competition from Uber and file a complaint with the Brussels prosecutor, regional transport minister Pascal Smet told Belgian newspapers Friday.

Smet told Le Soir that an examining magistrate could order a bank investigation and find out how many drivers were taking part in the system, their identities, and determine whether they were respecting fiscal and social security laws.

"The drivers are not paying tax on income," nor do they make social security contributions, he told the newspaper.

Smet said he would ask Belgian police to monitor the Uber website and that he would write to the Apple and Google stores to try to get them to deactivate the app that connects Uber with customers on smartphones.

"This application does not respect the law here," he said.

Founded in 2009 in California, Uber has become a popular transportation alternative to traditional taxis.

Uber charges a commission for each ride, but fees charged by the service's drivers are generally lower than normal taxis.

But legal clashes and controversy have started to cloud Uber's horizon.

It has been banned from operating in Spain and received a partial ban in Thailand.

Meanwhile the city government in New Delhi banned it from operating in the Indian capital after a passenger accused one of its drivers of rape.

The service has also hit regulatory hurdles in locations from Germany and the Netherlands to the US city of San Francisco, where a driver was charged in an accident leading to the death of a six-year-old girl.

A French court on Friday rejected a bid by taxi companies to have Uber's non-professional driver service UberPop banned.

Explore further Dutch judges ban taxi service UberPOP (Update)

© 2014 AFP