Parents have been warned not to allow babies or toddlers to passively watch TV or screens on other devices for any period of time.
The World Health Organisation (WHO) has said this could be a leading risk factor for obesity related ill-health.
It is one of several guidelines that the WHO is set to present at the European Congress on Obesity in Glasgow.
The WHO says that children under the age of two should not spend any time in front of screens. It added that screen time – including computer games – should be kept to under an hour for children aged 2-4.
It hopes the advice will help to tackle child inactivity, which can lead to obesity.
Another important piece of advice from the WHO is to limit the amount of time a baby is strapped into a buggy, car seat or sling as much as possible. It says babies should spend no longer than one hour at a time strapped in.
Babies should be active several times a day and have at least 30 minutes ‘tummy time’ where they lay on their front.
Dr Juana Willumsen was one of the authors of the guidelines.
She said: “Sedentary time should be made into quality time. Reading a book with your child, for example, can help them develop their language skills.
“A child who is given a tablet to keep them quiet while they are sitting in a pushchair is not getting the same [quality sedentary time].
“Children need to be given opportunities throughout the day to actively play and we should be reducing sedentary, passive screen time.”