In a victory for tobacco and restaurant lobbyists, the Cambridge City Council on Monday narrowly approved amendments significantly weakening what was to be the toughest anti-smoking law ever enacted in the city.

The altered ordinance loosens restrictions on smoking in restaurants and bars and removes a requirement that cigarettes and tobacco be located behind store counters throughout the city, allowing them to continue to be placed in open displays.

The tight votes split the council nearly evenly, with some council members voicing health concerns and others warning that city restaurants would lose the business of patrons who smoke if a tough measure were passed.

Opponents of the new watered-down ordinance signalled that they would reluctantly go along with the changes and not try to derail the bill. The council, which will vote on the altered bill next Monday, is expected to pass the new version.

The original ordinance would have restricted smoking to 30 percent of a restaurant's seats in the first year of enactment, and 15 percent of seating after the second year. But the amended version allows restaurants to designate up to half their seating for smoking, with no reduction over time.

Under the current law, passed in 1987, restaurants can reserve 75 percent of seats for smoking, although few designate more than 30 percent.

"It's lost a lot of effectiveness," said Kate Dempsey, coordinator of Cambridge United for Smoking Prevention (CUSP), a program of the Cambridge Substance Abuse Task Force involving city officials and community residents.

"Combating second-hand smoke is one of the most important public-health measures this city council can take," Councillor Francis H. Duehay '55 told the body. "I believe this compromise is wrong."

"We have a tremendous amount of restrictions already, and I think to add any more is a burden," replied Vice Mayor Sheila T. Russell.

The amended ordinance approved Monday night is the result of several revisions of CUSP's original proposal, submitted in March. The key modifications to the original proposal came from the pro-business Cambridge Chamber of Commerce and the Massachusetts Restaurant Association.

In addition, Philip Morris Inc., the New York-based tobacco company, telephoned Cantabrigians in the month before Monday's vote, telling them to voice their objections.

Provisions

A number of clauses in the original measure were left unchanged. Every tobacco vendor will be required to obtain a tobacco sales permit from the city. Vendors will also be required to demand proof of age, with photo IDs.

The ordinance also bans smoking in public workplaces, except where employees have no contact with co-workers. It also proposes to prohibit smoking in retail stores, hospitals, clinics, nursing homes, taxis and limousines.

The amended bill struck the goal of "creating an atmosphere which promotes smoke-free restaurants and strives towards the long-term goal of smoke-free dining throughout Cambridge."