The government's emergency task force is pursuing the possibility of using text messages to warn the public of looming national disasters, it emerged last week.

At the height of the water supply crisis, the task force met with mobile phone operators to see if it could send out texts urging people to turn off their taps to conserve water supplies, communications minister Eamon Ryan confirmed last week.

"Preliminary discussion with the industry indicated that this is not a simple task and that the infrastructure is not designed to broadcast short message service (SMS) messages simultaneously to all users of the mobile phone network," his spokeswoman said.

There were technology issues that needed to be addressed and in this instance the broadcasting network was used instead to get the message across.

"There were difficulties, as is the case when four and a half to five million messages need to be sent," Ryan said in the Dáil.

But the task force, which is headed up by defence minister Willie O'Dea, is continuing talks with the mobile phone companies to try and overcome such problems and allow the government to communicate directly with every person in the country in an emergency.

The opposition spokesman on communication, Simon Coveney, claimed that the technical infrastructure does exist to provide a communications channel directly from government.

Coveney pointed out that there are 117 mobile phones for every 100 citizens and that practically every person or household has a mobile phone.

"It is the obvious way to contact and alert people to warn them about emergencies," he said.

He added that the government also needs to have the capacity to require private phone companies to provide the network to government in the case of emergencies.