Dou Keying, a taxi driver who already takes most of his jobs through phone calls, said taking two orders each day is not a big issue to him.

But he believes there should be specific items in the regulation to make sure it is enforceable, such as matching the location of the driver and the passenger.

"I certainly do not want to drive 10 km to take a passenger who is only traveling 3 km. That's why I like working on the airport route, which is longer distance," Dou said.

Meanwhile, the blacklist system of passengers must be based on identities rather than phone numbers.

"What if the person dials from a different telephone number? In that case the punishment will be virtually non-existent," Dou said.

These revisions are being carried out as part of a series of measures by the city's transport authority to address the difficulty of hailing a taxi in the capital, particularly during rush hour.

The city's economic planning body is also holding a hearing on taxi-fare adjustments as a price hike is on the cards.