Drivers face longer queues on London's roads due to a rapid rise in the volume of private hire vehicles (PHVs), the Licensed Taxi Drivers Association's (LTDA) says.
The transport body's assertion follows official figures showing mini cab numbers have jumped by over a quarter in the last two years.
Motorists in the capital have had an additional 15,000-plus PHVs to contend with - a rise of 26%.
The 62,800 mini cabs on London's roads compares to just 22,500 taxis - a rise of just 1% over the same period - according to Department for Transport (DfT) data.
The figures endorse the results of a YouGov poll released earlier this month which showed most Londoners would pick a cab-summoning app such as Uber over a Black Cab .
LTDA general secretary Steve McNamara says the rise of mini cabs has brought a "detrimental" impact upon the city's traffic.
Uber counters that the new statistics underline its services are helping travellers in regions where transport connections are weaker than elsewhere. It says they show that there is consumer demand for a "cost-effective" and "convenient" method of getting around the capital.
Mr McNamara attributes the PHVs' growth to the way Uber and companies like them are luring new drivers through the prospect of unattainable earnings potential.
The official said some app firms are promoting a way-of-life dream that cannot be met in reality. Mr McNamara added that the capital's taxi numbers are dependent on the economy's health.
The DfT figures also show that London PHVs have risen by 57% over the last 10 years, whereas black cabs have seen growth of only 8%.
Licensed vehicle quantities have risen 9% between 2013 and March 31 of this year to 242,200 - the highest since records began.
Copyright Press Association 2015