Flouting the rule would attract fine and suspension, officials of the state transport corporations said today.
The decision was taken following a reported statement by a couple of passengers of the ill-fated bus who claimed that the driver was talking over his mobile phone while driving and lost control over the vehicle.
The bus had rammed into the railing of the bridge before falling into a canal in Murshidabad district's at Balirghat yesterday killing 42 passengers and injuring eight.
South Bengal State Transport Corporation (SBSTC) chairman Tamonash Ghosh told the PTI that that the rule will be implemented immediately and drivers would be suspended and fined if they were found using mobile phones while on duty.
"We currently have CCTVs installed in 120 buses out of a total 600. We will soon complete installing CCTVs in the rest of the buses. This will help us in keeping a tab of the behaviour of the drivers," Mr Ghosh said.
North Bengal State Transport Corporation (NBSTC) chairman Mihir Goswami said a directive has been sent to every division regarding banning the use of mobile phones by drivers while on the driving seat.
"The suspension will be for at least three to four months followed by a probe. If found guilty strict action will be taken," Goswami said and urged people to come forward and help them nab drivers who were found flouting the rule.