A complete ban on the smacking of children was necessary in order to give them the same protection as adults and to prevent physical abuse, the report by the Commission on Families and the Wellbeing of Children said.
Surveys show most parents would like to see a ban on smacking but the Government has so far resisted. Ministers have argued that it would be unduly intrusive to punish parents who discipline their children with a light tap or slap.
The present law, which took effect in England and Wales this year after earlier being implemented in Scotland, only bans smacking that leaves a physical mark such as a swelling or bruise. Mild smacking is allowed under a "reasonable chastisement" defence against common assault.
Sir Michael Rutter, the child psychiatrist who chaired the commission, said evidence showed that smacking children can "escalate to frank abuse". "Why is it alright to beat another child but not to beat another adult," he said yesterday.
The report says the present law is flawed because some children bruise less easily than others and there are "methods" of using violence that do not give rise to physical signs.
"Dealing with ... children in this way means they are excluded from normal human rights. The Government should remove the defence of reasonable chastisement in its entirety."
The commission rejects minister's fears that a total ban would mean parents being taken to court for trivial cases. With "appropriate guidance" to the Crown Prosecution Service such cases could be avoided as they are in the case of trivial assaults on adults, it says.
Some 350 children's organisations believe that all physical punishment should be banned.
The Commission, which was established by the Joseph Rowntree Foundation, also calls for the age of criminal responsibility to be raised from 10 to 12.
Under the current law, children under 10 cannot commit crimes because they are regarded as being too young to weigh up what is right and wrong.
But research from the Royal College of Psychiatrists cited in the report has shown that a child's understanding of crime may not be fully developed until they are in their late teens, even though a degree of "maturation" is achieved by age 14.Reuse content