Diplomats from the UAE and the UK have been successful in persuading the UN Human Rights Council to adopt a resolution backing 12 years of quality education for all girls.
"Today, the Council adopted, by consensus, a landmark resolution on girls' education led by the UK and the United Arab Emirates," said Simon Manley, the UK's ambassador to the UN in Geneva.
"For the first time ever in a UN document, the resolution calls for the international community to commit to 12 years of quality education for all girls wherever they are in the world."
Mr Manley thanked all delegations in Geneva for backing the motion and said the UK would host a major international education summit in two weeks. Educating girls, he said, was one of the smartest investments any country can make.
Earlier on Monday, Britain said it would give £15.8 million ($21.9m) in aid to support education in six countries affected by conflict, including Jordan, Lebanon and Syria.
The UK government said the funding would “address a chronic lack of research” into the most effective methods to teach young people in unstable areas.
The six countries – Myanmar, Nigeria and South Sudan being the other three – are home to about three million children who are refugees or displaced.
“We believe that every girl and every boy should receive a quality education, no matter where they live,” said UK Foreign Secretary Dominic Raab.
“This research will find better ways to teach the world’s most vulnerable children who are caught up in conflict and long-term crisis to receive a better education.”
Britain's Foreign, Commonwealth and Development Office said that children whose lives had been affected by wars, political unrest and natural disasters often suffered "a severe disruption to their learning, with lifelong consequences”.
Refugee girls, it said, were disproportionately affected, with half being out of school before the pandemic. An estimated 20 million girls are at risk of leaving school for good in the next year because of Covid-19, “leaving them more vulnerable to child marriage, gender-based violence, human trafficking and sexual abuse".
The pledge comes before the Global Education Summit in London later this month, which aims to raise $5 billion to support the activities of the Global Partnership for Education fund.
The £15.8m funding is part of the £400m that Mr Raab announced in April to support girls' education in the next year.
The UK government also announced £430m last month to help the Global Partnership for Education, which works to boost education in the developing world.
As the current president of the G7, the UK has sought to put education near the top of its agenda.