Angry taxi drivers shouted abuse at Boris Johnson today after he admitted he was powerless to stop minicab app firm Uber.
Traditional black cab drivers packed the public gallery at City Hall for the first Mayor's Question Time since the election.
The mayor was repeatedly heckled, with one cabbie yelling at him 'You're a joke, Boris'.
Johnson said trying to ban Uber was pointless because the company would find a way to continue operating.
The mayor's exchanges with taxi drivers became increasingly heated after he said the industry was governed by market forces.
Cabbies are planning a protest in Victoria on Tuesday.
Even if we get a judgement saying that Uber is illegal, I'm afraid that Uber will simply come back and change the model and you will have a situation in which the taxi meter is effectively being held in the hands of the passenger.