Investing in the first five years of a child's life has been proven as critical in providing all children an equal chance at success, no matter who they are or where they are born. To allow the brain to grow and the child to develop to their full potential, children need quality nurturing care - including play, health, protection nutrition and early learning.
However, whilst progress is being made in some areas, children's early learning is too often neglected, putting millions of children at a disadvantage before they even start primary school.
A pre-primary education has a significant impact on a child's future prospects both in their education and adult life. Benefits of investing in pre-primary education are found to be the greatest for the most disadvantaged, who are often the least prepared when starting primary school and therefore most likely to be left behind.
In Mozambique, for example, children in rural areas who had enrolled in pre-school were 24% more likely to enroll in primary school and show improved cognitive abilities and behavioural outcomes compared to children who had not.
World leaders have recognised the key role the early years play in tackling inequality by agreeing a crucial target within the Sustainable Development Goals (SDGs), they agreed that by 2030 they would "ensure that all girls and boys have access to quality early childhood development, care and pre-primary education so that they are ready for primary education."
But despite the evidence and rhetoric the data is telling a different story. Of the 193 countries that committed to the SDGs only 38 currently provide free, compulsory pre-primary education. And when it comes to international donors giving to pre-primary education the picture is equally depressing.
New research published this week by children's charity Theirworld shows that overseas development assistance to Early Childhood Development has gone up in recent years - which is good news. The progress has been driven by large increases in health and nutrition after dedicated campaigns to improve children's start in life. This is something to support.
But at the same time only 1% of all early year's aid goes to pre-primary education with a shockingly small number of donors supporting this crucial area. In 2016 only three donors disbursed more than US$5 million globally to pre-primary education. In contrast 29 donors disbursed more than US$5 million to health.
Both national governments and donors are perpetuating inequality in the education system and wider inequalities by failing to support pre-primary for all children, instead they are disproportionately investing in higher education, which favours children from wealthier income groups.
Currently international donor governments give 26 times more to scholarships to help students study in rich countries in 2015 than to pre-primary. Poor children missing out on early years education are much less likely to reach higher education. In sub-Saharan Africa, only 1% of the poorer half of the population will enter into higher education - but this sector receives disproportionately higher levels of funding.
A new approach to education funding is needed urgently if we want to tackle inequality, with a greater measure of funding going to children at risk of being left behind, those living in rural areas, those discriminated against, children impacted by HIV/AIDs, girls and those facing multiple disadvantages.
This means countries must increase the amount and the percentage of their total education spending towards free and compulsory pre-primary services - and ensure funds are targeted towards children who need the most help. International donors have to do the same, increasing their share of education spending going to pre-primary to 10%.
The establishment of the International Finance Facility for Education (IFFEd) - similar to the one that exists for funding global vaccines - will help to fund overall education spending and be able to better target resources to pre-primary education. International donors have an opportunity to come behind the launch of the fund at the G20 in Argentina later this year.
We have seen tremendous progress in health and nutrition with concerted global campaigns making breakthroughs in tackling preventable child deaths and malnutrition. Now is the time to build on this progress and deliver quality pre-school services to all children, no matter who they are or where they are born.
Graça Machel if the founder and president of the Foundation for Community Development and the Zizile Institute for Child Development. She founded the Graça Machel Trust in 2010 where she focuses on child protection and development, women's economic and financial empowerment, food security and nutrition, leadership and governance.
Any views expressed in this article are those of the author and not of Thomson Reuters Foundation.