TORONTO — Drivers in Ontario soon could be banned from chatting on a hand-held cellphone, text-messaging on a BlackBerry or hunting for street addresses on a GPS navigation device while behind the wheel.

Premier Dalton McGuinty announced yesterday that he is considering joining many other jurisdictions that have introduced legislation requiring drivers to use a headset or speaker system when talking on cellphones. But he wants to go much further by banning not just hand-held cellphones but every other electronic device that has the potential to distract drivers.

As recently as April, Mr. McGuinty said banning drivers from using cellphones in Canada's most populous province was not on his agenda. He said there was little point in such a ban because drivers engage in all kinds of other activities behind the wheel that are just as distracting, including drinking coffee or applying lipstick.

But he has changed his mind after a recent spate of fatal automobile accidents in which drivers were suspected of talking on the phone.

"I've always said I'll do what the police think is important and make our roads safer," Mr. McGuinty said yesterday.

Police officials in Ontario have advised him not to zero in on just cellphones, but all the other gadgets used by multitasking drivers.

Among those drivers are the ones who have been known to read road maps while behind the wheel. He has asked Transportation Minister Jim Bradley to look at "next generation" legislation that would take into account existing electronic devices as well as those still on the drawing board.

"What about people who are tapping on the GPS system? What about the next gadget that they haven't invented yet?" he asked. "I know what they've done in other provinces and other states. They've just dealt with one item - a cellphone."

In 2003, Newfoundland and Labrador became the first province to ban hand-held cellphones behind the wheel. Penalties in the province range from a minimum fine of $11 to a maximum of $400 plus four demerit points. Quebec and Nova Scotia have joined Newfoundland. Manitoba is considering a similar ban amid compelling evidence that distracted drivers are a danger on the road.

Quebec's coroner's office has blamed cellphones for 24 fatal car crashes in the province between 2000 and 2006. In the United States, the National Highway Transportation Safety Administration estimates that driver distraction contributes to about one-quarter of all collisions.

Other research studies suggest that the risk does not stem solely from whether one or both hands are on the steering wheel, but rather the conversation itself. However, it is far more likely that a driver in an accident will be talking to someone on a cellphone rather than in the passenger seat.