Campaigners have been calling for a complete ban on selling energy drinks to children due to their high sugar and caffeine content.
And now Waitrose has announced it will stop selling high-caffeine energy drinks to children aged under 16. From March 5, the supermarket will ask customers buying drinks containing more than 150mg of caffeine per litre to prove they are over 16.
Waitrose said its decision was built on existing industry labelling guidelines, which require any soft drink with more than 150mg of caffeine per litre to carry a high-caffeine content warning and state it is not recommended for children.
The British Soft Drinks Association introduced a voluntary code of practice in 2010 stating that high-caffeine soft drinks should not be promoted or marketed to those under 16.
Simon Moore, Waitrose director of technical and corporate social responsibility, said: "As a responsible retailer we want to sell these products in line with the labelling guidance.
"These drinks carry advice stating that they are not recommended for children, so we're choosing to proactively act on that guidance, particularly given the widespread concerns which have been raised about these drinks when consumed by under-16s."
Teachers' union NASUWT welcomed Waitrose's move, saying that one in 10 teachers cited energy drinks as a key cause of poor pupil behaviour in schools.