The running battle between Transport for London (TfL) and Uber has flared up once again.

TfL has opened a consultation on rules for private hire vehicles which, if adopted, would amount to a severe crackdown on the insurgent firm.

The rules include English language skills for drivers, stricter insurance requirements, a map reading test, demands for a landline, and the ability to book a vehicle up to 7 days in advance.

Garrett Emmerson, TfL’s chief operating officer for surface transport, said: "In recent years the private hire industry has grown exponentially and technology has also developed rapidly. The consultation sets out a number of ways that standards across the industry could be raised, ensuring Londoners can continue to benefit from the service provided by licensed private hire vehicles."

Black cabs drivers have made their unhappiness at Uber clear in large protests around the capital, and the proposed new rules are being seen as a direct attack on Travis Kalanick’s firm.

Jo Bertram, regional general manager, UK, Ireland and Nordics, at Uber said: "These bureaucratic new rules will not improve your ride. They’re designed to address the concerns of black cab drivers, who feel under pressure from increased competition. But the answer is to reduce the onerous regulations cabbies face today – not increase them for everyone else."