Toddlers should not be allowed to watch screens at all, Sweden told parents on Monday.

Children under the age of two should be kept away from digital media and television completely, the country's Public Health Agency said.

Kids between the ages of two and five should be limited to a maximum of one hour of screen time a day, it said in new recommendations, while those aged six to 12 should spend no more than an hour or two a day in front of a screen.

Teenagers aged 13 to 18 should be limited to two to three hours per day, the agency said.

"For too long, smartphones and other screens have been allowed to enter every aspect of our children's lives," Public Health Minister Jakob Forssmed told reporters.

The minister said that Swedish teens aged 13 to 16 spend six and a half hours a day on average in front of their screens, outside of school hours.

Forssmed said that didn't leave "a lot of time for communal activities, physical activity or adequate sleep", and lamented a Swedish "sleep crisis" noting that more than half of 15-year-olds did not get enough sleep.

The health agency also recommended that kids not use screens before going to bed and that phones and tablets be kept out of bedroom at night.

It cited research showing that excessive screen use can lead to poor sleep, depression and body dissatisfaction.

Sweden's government has previously said it is looking at a ban on smartphones in primary schools.