Nobel Peace Prize winner Malala Yousafzai wants world leaders to spend more money, on top of their earlier promises, to secure 12 years of free primary and secondary education for all children across the world.

The Pakistani teenager who was shot by the Taliban in October 2012 for asserting her right to an education says she will continue her fight for children's right to education and ask world leaders to invest an additional $39 billion annually.

"We will not stop. We will continue to speak out and raise our voices until we see every child in school," she said ahead of an education summit in Oslo, Norway, attended by U.N. Secretary General Ban Ki-moon, among others.

An estimated 58 million children aren't going to school. While aid for basic education had doubled from 2002 to 2009, it has since stagnated and fallen in recent years, according to a summit paper. Even though many countries have increased their national budget allocations, progress in getting more children to school has stalled.

Universal fee-free primary and secondary education for a 12-year period costs an estimated US$340 billion per year through 2030, according to the Malala Fund, the nonprofit organization she co-founded. Low- and lower-middle-income countries must commit a minimum of 20 percent of their national budgets to education, against the current average of 15 percent.

Governments must "start investing in books, education and hope, rather than in weapons, war and conflicts," Malala said, reiterating that some 100 countries in May committed themselves to provide free primary and secondary education to all children by 2030.

Malala and India's Kailash Satyarthi were awarded the Nobel prize in 2014 for helping protect children and advance their education.