People who send text messages while driving take their eyes off the road up to 400% more than other drivers, the Road Safety Authority (RSA) has said.

From today (May 1), tough new penalties have been introduced to deal with drivers who engage in this type of dangerous behaviour.

Until now, it has been an offence to hold a mobile phone while driving. However, the rules relating to text messages did not apply specifically to phones that were not held, i.e. that were kept in a phone cradle in a vehicle.

These new rules close that loophole, which may have allowed drivers to send a text message if the phone was in a cradle. They apply specifically to SMS (text) or MMS (multimedia) messages and emails.

According to the rules, any person caught texting while driving must attend court and they will face a financial penalty of up to €1,000 for a first offence. They will not have an option to take the lesser penalty of penalty points on their licence.

The regulations do not make it an offence to speak via a phone hands-free device. It is also not an offence to touch a button on a hands-free device in order to answer a call.

The RSA insisted that texting while driving is ‘one of the most dangerous things a motorist can do'.

"It's lethal behaviour, even when stopped in traffic, and it's in all our interests to put the phone away while driving," it said.