United Private Hire Drivers, a branch of the Independent Workers Union of Great Britain, claims that the rule change indirectly discriminates against ethnic minority drivers and breaches their human rights.
The drivers are currently exempt from paying the congestion charge while travelling in central London.
But under new rules, which come into force from 8 April, they will have to pay the £11.50 daily charge.
Black cab drivers, in contrast, will continue to be exempt from paying the charge.
“The IWGB today issued a pre-action letter giving the Mayor until 6 March to reverse the policy before the union launches a judicial review in the High Court,” a spokesperson for the union said.
“The introduction of the £11.50 congestion charge on minicab drivers is a case of indirect discrimination under the Equality Act.
“The charge is being imposed on a workforce that is mainly Bame… while black cab drivers, who are mostly white, continue to be exempt.”
Around 94 per cent of London’s minicab drivers are from ethnic minority backgrounds, according to Transport for London (TfL).
“Uber drivers like myself are being squeezed,” said Muhumed Ali, a minicab driver and IWBG member.
“On one side we have the company that keeps us earning poverty wages and now, on the other, we have the TfL and mayor Sadiq Khan looking to charge us £11.50 when we go into central London.”
“Newsflash Sadiq Khan: private hire drivers are no longer prepared to be the easy target cash cow you and TfL have treated them in the past!” James Moyer-Lee, IWBG’s general secretary, said on Twitter.
The changes to the congestion charge were proposed by Mr Khan and TfL to reduce congestion and air pollution in central London.
“The number of Private Hire Vehicles entering the Congestion Charge zone has shot up from 4,000 a day in 2003 when it first came into operation, to more than 18,000 now,” a spokesperson for the mayor of London said.
“Sadiq simply isn’t prepared to ignore the damaging impact this has on congestion and increasing air pollution.
“Congestion has a crippling impact on businesses across the capital. At the same time, our toxic air in London is a major public health crisis that is stunting the lung development of our children, leading to thousands of premature deaths and increases the risk of asthma and dementia.
“Most other motorists, from private cars to small business owners, are liable for the Congestion Charge. Removing the Congestion Charge exemption for private hire vehicles is a key part of our plans to both reduce congestion and to protect Londoners from harmful emissions from polluting vehicles.”
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