Parents of under-fives in England are to be offered official advice on how long their children should spend watching TV or looking at computer screens.
The government says it will publish its first guidance on screen time for the age group in April.
It comes as government research was published showing that about 98% of children under two were watching screens on a daily basis - with parents, teachers and nursery staff saying youngsters were finding it harder to hold conversations or concentrate on learning.
Children with the highest screen time - around five hours a day - reportedly could say significantly fewer words than those at the other end of the scale who watched for around 44 minutes.
