Tanzania has banned the smoking of shishas or water pipes over concerns of links with drug or alcohol abuse.
The government said businesses in the country's biggest city, Dar es Salaam, were expected to stop shisha sales within seven days.
Shisha smoking has become increasingly popular with young people in Tanzania.
But there has been growing concern that smoking the fruit-scented tobacco through a bowl and tube could be used to cover up alcohol or drug abuse.
The BBC's Tulanana Bohela in Dar es Salaam says there have been cases of some users replacing the water with alcohol or marijuana infused water.
Prime Minister Kassim Majaliwa is reported to have said that shisha smoking was killing future generations.
Shisha smoking is common in many Arab countries and in Tanzania was traditionally an activity associated with Arab or Asian groups.
However, as in Europe, it has grown in popularity across society in recent years.
Health campaigners in the UK have warned of the dangers of smoking shishas, also known as hookahs, narghiles, arghilehs or hubble bubbles.
Doctors say there is a "misconception" that shishas are not as harmful as cigarettes and the British Heart Foundation says an hour-long shisha session can be the equivalent of smoking more than 100 cigarettes.
"Traditionally shisha tobacco contains cigarette tobacco, so like cigarettes it contains nicotine, tar, carbon monoxide and heavy metals, such as arsenic and lead," it says.
"As a result, shisha smokers are at risk of the same kinds of diseases as cigarette smokers, such as heart disease, cancer, respiratory disease and problems during pregnancy."