The "Education Cannot Wait Fund" will seek to raise $3.85 billion over five years from leading governments, companies and philanthropists.

It will be formally launched next week at the World Humanitarian Summit to be held in Istanbul.

Sending Syrian children living in camps in Jordan, Turkey and Lebanon to school would cost about $800 million per year, Brown told reporters.

The goal is to provide hope to a "lost generation" of children stranded in camps without access to schools, he said.

The fund is aimed at sustaining school-age children for up to five years and marks a shift from providing short-term emergency humanitarian aid.

Some 75 million children worldwide have seen their education severely disrupted by wars, natural disasters and other crises.