The Government plans, which follow the announcement of a social media ban for under 16s, also include a crackdown on addictive features.

Technology secretary Liz Kendall said: ‘These measures will be crucial in helping young people get the sleep they need, focus on school and college, and spend more quality time with family and friends, all of which are fundamental to building a happy, healthy and fulfilling adult life.'

Features that can keep users scrolling for longer - such as videos that automatically play one after another and feeds that continually serve up personalised content - will also be switched off by default for older teenagers.

Other protections include regular breaks for under-18s using chatbots and a clampdown on services that provide dangerous, misleading or unverified mental health advice.

The measures are designed to ensure 16 and 17 year olds do not face a cliff edge of being exposed to the most addictive online features.