Opponents of the smoking ban in Northern Ireland have slammed the introduction of the new law.
Simon Clark, director of the smokers' lobby group Forest said: "The ban makes Northern Ireland a less liberal, more intolerant place.
"Tobacco is a legal product and it is very sad that there is not a single pub, club or bar in the country where anyone can light up without being fined.
"The ban is undemocratic because government research shows that a clear majority favour a choice of smoking and non-smoking facilities in pubs and clubs."
Clark said that smoking bans in Scotland and the Republic of Ireland have had little impact on smoking rates.
"Some smokers will quit but the vast majority have no intention of giving up. A great many people enjoy smoking and they are fed up being told what to do by politicians and health fanatics. Far from giving up, many smokers will be reaching for their fags in defiance.
"Some local communities will undoubtedly suffer because the ban will be the last straw for many pubs, especially in rural areas.
"If Scotland is anything to go by, bingo halls and working mens' clubs are also at risk. Unfortunately the war on tobacco is now so extreme that any attempt to find a compromise is dismissed out of hand."
Clark appealed to local authorities to view favourably planning applications by pubs and clubs for outdoor smoking areas.
"We want people to smoke responsibly in as much comfort as possible. Government has a duty to educate people about the health risks of smoking, but it doesn't have the right to bully people into giving up."
Musician Joe Jackson, a supporter of Forest and an outspoken opponent of smoking bans in America and the United Kingdom, said the anti-smoking lobby represented a "fanatical fringe".
He said: "Britain is becoming a society in which the extreme agendas of health officials and pressure groups are allowed to determine public policy. Freedom of choice, tradition, tolerance, pleasure, property rights, market forces and public opinion are being swept aside by a fanatical fringe."