Cabbies to be taught when to shut up

London cabbies could soon face mandatory lessons on when to shut up under proposed measures to boost customer service.

The capital's taxi drivers - renowned for their willingness to share their thoughts - would also learn how to welcome passengers and deal with stressful situations.

Cabbies must already demonstrate 'the Knowledge' of thousands of streets and routes in the city, which takes up to three years to acquire.

However, head of taxi regulation at Transport for London John Mason told the Financial Times that the regime did not fully prepare drivers for life in a modern service industry.

"It's a world-renowned service. The drivers are always perceived to be some of the great characters you come across in London," he said, but cautioned: "There is always room for improvement. Perhaps it is good sometimes to keep your mouth shut if you sense vibes from the customer that perhaps they are having a bad day."

General secretary of the LTDA Bob Oddy said his organisation would not object to customer service training for new drivers.