Quit-smoking helpline number on India cigarette packs
India says tobacco firms must print a helpline number to combat smoking on all cigarette packs from 1 September.
The health ministry has also released new pictorial warnings, showing images of diseased organs and rotting teeth.
The government has asked companies to continue covering 80% of the surface of the packs with picture and text warnings.
India has more than 100 million smokers and the government says smoking kills nearly a million people every year.
All cigarette packs will have the words "tobacco causes painful death" printed on them along with the helpline number, 1800-11-2356, the government has said.
It added that any company failing to follow the new guidelines would be prosecuted.
In recent years, India has come up with stringent rules to curb the use of tobacco.
It made graphic pictorial warnings mandatory on all cigarette packs in 2014, but the decision was challenged by tobacco firms in the Supreme Court.
In 2016, the court rejected the tobacco industry's argument that the rules were impractical to implement.
Tobacco-related advertisements are also banned and it's a criminal offence to sell tobacco products to minors.
A countrywide ban on smoking in public places came into effect in 2008 - although correspondents say it is blatantly flouted and poorly enforced.