Plans to cut the speed limit in Dublin city to 30km per hour have been described as "farcical" and "devastating" by interest groups who say it will cause a backlash.
The proposed plans by Dublin City Council (DCC) went out for public consultation yesterday.
While the speed limit is already in effect in the main business and shopping districts, the new phase of speed zones could go out as far as Kilmainham on the southside of the city and Stoneybatter on the northside - as far as both the Grand and Royal canals.
The next phase for 2017 will cover Crumlin, Ballsbridge, Raheny, Beaumont and parts of Phibsboro and Drumcondra.
Conor Faughnan of AA Roadwatch said the speed cutting measures are "clumsy and unnecessary" and have effectively coloured in the whole city.
"It will carelessly apply 30kph limits on clearly unsuitable roads," Mr Faughnan said.
"When the flurry of bonkers 30km signs appear on unsuitable roads everywhere there will be a backlash. Use 30kph limits, use lots of them - probably in 90pc of the city centre.
"But do it in the right way and don't delude yourself that by putting a silly number on a pole you have done something good for road safety."
Taxi drivers have also come out vehemently against the measures, with Christy Humphreys of the National Private Hire and Taxi Association (NPHTA) saying it will be "devastating" trying to take fares around the capital and will add to costs for both the drivers and customers.
"We're very much against it," Mr Humphreys said. "Like everything else, we'd like to see the reason for it. I don't see why - people just want to get in and out of town in a hurry. It's not an accident problem with collisions every day of the week."
Fianna Fail transport spokesman Robert Troy said that speed limits in isolation will not solve the safety or congestion issues in the city.
"We have to look at a wider strategy and plan a way to alleviate congestion - because at the moment introducing 30km speed limits on its own won't work," Mr Troy said.
"You have buses and lorries eliminating cycle lanes and you have cyclists coming in and out of traffic that's parked up - and sometimes you have pedestrians who will use a traffic jam to walk in and out of cars. Of course it leads to safety issues."
Mr Troy has called on all interest groups to make submissions.
Some members of the public who drive through the city for work reacted with dismay at the proposals yesterday.
Engineer Larry Joyce, who works in the city, said people might get too preoccupied with the speed limit.
"Who comes up with these ideas? People will end up spending more time checking their speedometers than looking at the road ahead of them, and that is surely more of a danger," he said.
Mick McDonnell of Dynamic Cleaners told the Herald he already has to start early to get into the city with the present speed limits.
"I start work at 3.30 and 4am in the morning, because it's so hard to get around the city at other times of the day," he said.
Taxi driver John Lynch said the idea would have drivers "crawling" with their customers through the city, saying: "It's a farcical plan. You could walk quicker than 30km an hour. Traffic is so bad you can't even get up to that speed."
In response to the comments from the AA, a DCC spokeswoman said: "While it is correct to state that road safety is a pertinent motivation for this proposal, it is also equally important to inform the residents of Dublin as to the benefit of a calmer environment around their homes, so that children may feel safer when walking or playing near their homes.
"In terms of the accusation that we have 'essentially coloured in the whole of the city centre', this is a total misrepresentation of the facts as we have deliberately excluded the main arterial routes from our proposal."