A ban on smacking children has been backed by the Liberal Democrats at their conference in Brighton.
The party says a law dating back to 1860 which allows "reasonable chastisement" of children should be scrapped.
The call follows pressure for the abolition of the law from the United Nations and European human rights groups.
Laws to protect children from physical punishment have been passed in 10 other European countries.
Liberal Democrat spokesmen for children, Paul Burstow MP, said: "This debate
goes to the heart of modern liberal values.
"It is a terrible indictment of our society that, though smaller and more
vulnerable, children still have less protection under the law.
"We are not pleading a special case for children, just equality and the
freedom to grow up without violence.
Mr Burstow said that there had been occasions when he hit his own children but he now regretted it.
He said: "I did it because I was tired and frustrated - that's why most
parents who hit their children do it."
The MP added that a ban, whilst not preventing all incidents, would help parents to "think twice about lashing out when they are at the end of their tether".
"What changing the law does, as we have seen in Sweden, is it provides the
backbone to the educational campaigns by sending out the message as a society
that it is not OK to hit a child," he said.
Baroness Walmsley, co-sponsor of the motion, said: "The existence of
so-called 'reasonable chastisement' in law encourages the disturbing levels of physical punishment in our homes.
"Learning from Europe, we should scrap this archaic law to discourage hitting children and help us promote positive and more effective forms of discipline.
"The law educates and sets standards in all spheres of society, including how
we behave in the home.
"In the 21st Century, our children deserve far better than a law designed when we were still sending them up chimneys."