One of Europe's toughest anti-smoking laws has gone into effect in Italy, although many bar and restaurant owners say they intend to ignore the ban.

As of today (Monday), smoking is prohibited in offices, restaurants, theaters and all other public places. Those who disregard the law risk large fines, but smoking is still permitted outdoors, in private homes or in restaurants that install specially-ventilated smoking rooms.

About one-quarter of all Italians smoke, and Health Minister Girolamo Sirchia says cigarette smoking is the nation's top cause of preventable death.

The minister, a physician, says the new law aims to protect non-smokers, who are -- in his words -- being poisoned by second-hand smoke.

The new law originally was supposed to take effect on January 1, but enforcement was delayed so smokers could enjoy their New Year celebrations.