President of the Philippines Rodrigo Duterte attends a news conference Reuters

Philippine President Rodrigo Duterte has signed an executive order banning smoking in public across the second-most populous country in Southeast Asia, one of the region's strictest anti-tobacco laws.

The presidential spokesman Ernesto Abella said on Thursday that the ban, which carries a maximum penalty of four months in jail and a fine of 5,000 pesos (US$100), covers both indoor and outdoor smoking.

The order also covers existing bans on tobacco advertisements, promotions or sponsorship that are subject to fines of up to 400,000 pesos along with a jail term of maximum three years. Revocation of business permits is also possible.

Abella said that the current ban replicates an ordinance Duterte created in 2012 in his southern hometown of Davao City. Although, Duterte himself a heavy smoker but, he quit smoking when, he was diagnosed as suffering from Buerger's disease that can cause blockages in the blood vessels.

The 71-year-old leader campaigned for the presidency promising to be tough on criminals, the corrupt, and drug pushers and users and to uproot vices one by one, such as smoking and illegal gambling.

The Philippine Tobacco Institute was not immediately available for comment. There are eight firms making cigarettes in the Philippines.

According to the order signed on Tuesday, the designated smoking areas not larger than 10 sq m (12 sq yards) will be set up for adults only and must be at least 10 metres (11 yards) from building entrances or exits. Police-led anti-smoking task forces will be created in towns and cities.

The authorities said the smoking ban also covers "vaping" or the use of electronic cigarettes. It will apply in casinos, including gaming floors and entertainment rooms, and inside airport buildings, except in designated outdoor smoking areas.

Philippine public health campaigners have been battling for a long time against the hefty tobacco lobby. They have welcomed Duterte's push to end smoking in public.

A 2014 report by the Southeast Asia Tobacco Control Alliance shows that there are about 17 million Filipino smokers, or nearly a third of the adult population. Nearly half of all Filipino men and 9 percent of women smoke and experts say the habit costs the economy nearly US$4 billion in annual healthcare and productivity losses.

Marlboro owner Philip Morris International, which is estimated to hold more than seven-tenths of the Philippines market through its Fortune Tobacco joint venture, will be among the international producers most affected.

In 2015, the Philippines accounted for almost one in every 13 cigarettes sold by Philip Morris globally, though analysts estimated that was worth about 2 percent of profit.