Parents will be prosecuted if they fail to prevent their daughter from being subjected to female genital mutilation, while all victims of FGM will receive lifelong anonymity, David Cameron will announce on Tuesday (22 July).
The prime minister will host the UK's first Girl Summit with Unicef, aimed at mobilising domestic and international efforts to end FGM and child marriage.
To mark the conference, Cameron will announce a change to the law, which will make it the responsibility of the parents to protect their children from FGM. The new legislation extends sanctions as it is already against the law to cut a child in Britain or to take a child out of the country for FGM.
Cameron will also launch a £1.4m "prevent programme" to help eradicate the practice and to care for survivors. A new specialist FGM service, which will include social services, will identify those at risk of being cut.
He is also expected to unveil new guidelines for police on how to handle new cases, as well as a consultation on civil orders to protect those at risk of cutting.
An "international charter" calling for the eradication of FGM and forced marriage within a generation will also be announced, with programmes to identify child and forced marriage in 12 developing countries.
The summit, the first of its kind to be held in Britain, will be attended by international politicians, women who have undergone genital cutting and campaigners, including the Pakistani teenager Malala Yousafzai.
Speaking ahead of the conference, Cameron said: "All girls have the right to live free from violence and coercion, without being forced into marriage or the lifelong physical and psychological effects of female genital mutilation.
"Abhorrent practices like these, no matter how deeply rooted in societies, violate the rights of girls and women across the world, including here in the UK."
Phumzile Mlambo-Ngcuka, the executive director of UN Women, said the situation is improving but many girls remain at risk.
"There's traction and more people that are willing to take a stand, but not enough yet," she said, as quoted by BBC News.
"The fact that 30 million girls are at risk of being cut in the coming years clearly means that we have a big challenge on our hands."
The new measure comes the day after it emerged that the number of women living in England and Wales who are living with FGM is double the number previously thought.
Research by City University London in collaboration with the charity Equality Now revealed 137,000 women are living with the consequences of the procedure.
Census information published in the report also showed that the number of women born in countries within the Horn of Africa, where FGM is almost universal, had increased by 34,000 ‒ from 22,000 in 2001 to 56,000 in 2011.
Home Secretary Theresa May, Deputy Prime Minister Nick Clegg and Justine Greening, the international development secretary, will also appear at the summit.