GMB, Britain’s general union, has instructed law firm Leigh Day to take the first step in launching legal proceedings on behalf of three Addison Lee workers whose contracts were terminated following a GMB protest in Berkeley Square in May.

The union's lawyers have lodged a number of claims with arbitration body ACAS including unfair dismissal, detriment on grounds related to trade union activity and failure to pay the national minimum wage.

The dismissals took place within hours of a static protest in May that saw private hire drivers block off Russell Square in London.

GMB members, along with members of the United Addison Lee Drivers (UALD), were protesting against an increase in commission levels from Addison Lee and changes to terms and conditions for drivers.

Gary Pearce, GMB regional officer, said "Addison Lee has been caught red handed, unfairly targeting and punishing private hire drivers simply for seeking to protect their rights at work.

"By victimising those who simply want a fair deal and to prevent exploitation, the company is seeking to bully its remaining workers into silence.

"Addison Lee’s attitude towards these drivers is completely unacceptable. This naked attempt at union busting has no place in the modern world of work."

Chris Benson, head of employment at Leigh Day, said: "These three men were trained by Addison Lee, they were required to work on standard terms which were dictated by Addison Lee and had to work to detailed practices, policies and procedures imposed by Addison Lee. They cannot then be sacked without notice or reason.

"Employers cannot be allowed to have all the financial benefits of employees and none of the responsibilities to these people’s livelihoods.

"The attempt to reframe normal employment as part of the gig economy is a serious threat to the financial security of thousands of hard working people and will end up costing the taxpayer huge sums whilst companies take all the profit."