Schools should ban "harmful contact" from rugby games, experts have said.

In a new opinion piece published in a leading medical journal, academics said that tackles and scrums should be prohibited on school playing fields.

Allyson Pollock and Graham Kirkwood from the Institute of Health at Newcastle University argue that most injuries in youth rugby occur due to the collision elements of the game.

Writing in the British Medical Journal (BMJ), they said that ministers should "put the interests of the child before those of corporate professional rugby unions".

Removing collision from school rugby is likely to "reduce and mitigate the risk of injury" in pupils, they said.

They argue that a history of concussion is associated with the "lowering of a person's life chances" across a number of measures including low educational achievement and premature death. Meanwhile, a head injury is linked to an increased risk of dementia, they added.

Citing previous reserach into sports injuries in youngsters, the pair argue that rugby, along with ice hockey and American football, have the highest concussion rates.

They said that rule changes in collision sports can "make a difference", highlighting the Canadian ban on 'body checking' - where a player deliberately makes contact with an opposing player - in ice hockey for under 13 year olds.

Meanwhile, the evidence for other strategies to reduce concussion risk in contact sport - such as mouth guards - is "weak", the article adds.

And in the UK "teacher training in the skills of rugby are lacking, as is concussion awareness training," the pair wrote.

The researchers called on the UK chief medical officers to advise the UK Government to remove "harmful contact" from the game.

In 2016, the nation's most senior medics rejected a call for a ban on tackling in youth rugby.

But Professor Pollock, who has been researching injuries and rugby injuries for more than ten years, and senior reserach associate Mr Kirkwood said that under United Nations conventions, governments have a "duty to protect children from risks of injury".

"We call on the chief medical officers to act on the evidence and advise the UK government to put the interests of the child before those of corporate professional rugby unions and remove harmful contact from the school game," they wrote.

"Most injures in youth rugby are because of the collision elements of the game, mainly the tackle.

"In March 2016, scientists and doctors from the Sport Collision Injury Collective called for the tackle and other forms of harmful contact to be removed from school rugby. The data in support of the call is compelling."

Commenting on the article, Professor Tara Spires-Jones, UK Dementia Research Institute programme lead and deputy director of the Centre for Discovery Brain Sciences at the University of Edinburgh, said: "Very strong, reproducible evidence supports a greater risk of dementia in people who have head injuries in their lifetimes, which urges caution in games where there is a significant risk of head injury.

"However, the data on specifically whether playing rugby or other contact sports in school increases your risk of dementia are not as robust yet due to a lack of large prospective studies. It is also very clear that there are many health risks of leading a sedentary lifestyle."