SEOUL (AFP) - Students and teachers in South Korea will need to find new ways of staying alert through the long school day, after the government said on Friday (Aug 31) that it will ban coffee sales in schools.

Selling highly caffeinated drinks to students in schools has already been banned since 2013, but with coffee vending machines still available for teachers, wily students have been able to get around the rules and find their coffee fix.

Now the government wants to rule out any possibility of children buying highly caffeinated drinks on campus, a spokesman from the Ministry of Food and Drug Safety said, warning that students were turning to caffeine to stay up late studying and preparing for exams.

Under the move, which will take effect from Sept 14, coffee sales will be entirely prohibited from elementary, middle and high schools.

"Coffee will disappear from cafeterias and vending machines installed at schools", the spokesman told AFP.

South Korean newspaper Chosun Ilbo said students tend to resort to "energy drinks" and coffee containing milk to burn the midnight oil during examination periods.

The ministry warned of the health impacts of too much coffee, saying excess intake could cause nausea, an irregular heartbeat and sleep disorders.

South Korea is the seventh biggest importer of coffee in the world, according to the Korea International Trade Association, importing some US$700 million (S$960 million) worth of coffee in 2017.

KITA says South Koreans drank an average of 512 cups of coffee each last year.