Former UK prime minister Gordon Brown has announced that "child marriage-free zones" are to be set up in Pakistan.
Mr Brown, the UN's special envoy on global education, said the practice of forcing girls into marriage is "not acceptable in the modern world".
"It deprives a girl of her education and her childhood," he told the BBC.
Speaking on a visit to Islamabad, he revealed the UN is giving $10m (£6m), and the EU 100m euros (£83m), to get more Pakistani children into education.
"What we want to do is to encourage girls themselves to be aware of their rights, to encourage teachers and girls to work together to say that when people try to force them into early marriage, it's not acceptable," he said.
"And so in Pakistan, we are going to do a pilot project where we declare an area to a marriage-free zone, a child marriage-free zone."
He added that there was support for such a scheme in Pakistan and that funding for it would be made available.
Child marriage-free zones have already been set up in other countries, according to the former Labour leader.
Mr Brown said: "There are groups in Pakistan who want to make it easier for people to sell off their children in marriage at an early age, and that is not acceptable.
"It deprives a girl of her education and her childhood and indeed changes her life, and is something that is not acceptable in the modern world.
"So as part of our campaign to get every child at school, we want to remind people that the world does not want girls to be married as girls, as brides when they should be at school."
There is greater support amongst the general public for a ban of forced marriage for girls, Mr Brown believes.
"I think that people are realising that it is unfair for a girl to be pushed into marriage when she's still a child," he added.
There has been a global commitment to get every child into education by December 2015, which the UN and EU money will help to achieve, said Mr Brown, who is visiting Pakistan at the invitation of prime minister Nawaz Sharif.
"There are seven million children who are not going to school," he said. "This is completely unacceptable in the modern world and I know the prime minister wishes to do something about it.
"What we've got to do is find a way that Pakistan can increase the money its spending on education and we can give support from the international community for them to do so.
"We don't want girls forced into early marriage, we don't want child labour, we don't want girls and boys that are trafficked, we want schools that have teachers and we have got to make a huge impact on this problem as quickly as possible."