Pressure is mounting on HMRC for refusing to investigate Uber's approach on Value Added Tax (VAT) as the minicab firm starts another legal challenge made against them.
Uber have long maintained that it does not need to pay VAT as its drivers acts as a self-employed agent.
The current VAT threshold stands at a turnover of £83,000 each year, a total rarely achieved by its drivers.
However, a high profile ruling last year has changed its drivers employment status to 'workers' rather than 'self-employed'.
Uber have confirmed that there has been dialogue with HMRC, but never a formal investigation into how the company pays its tax.
Meg Hiller, the Labour MP for South Hackney and Shoreditch said it was 'extraordinary' that Uber have not been subjected to any formal investigations.
In an article in the Financial Times, Meg Hiller went on to say "HMRC has been slow to react to new business models."
A crowd funded appeal against Uber has now been lodged by tax barrister Jolyon Maugham who has demanded Uber pay the VAT owing.