The prolonged closure of the Strait of Hormuz has accelerated fears of an impending food crisis in some of the world’s poorest countries, with tens of millions of people at risk.

Small-scale farmers across Africa — responsible for feeding much of the continent — are struggling amid a shortfall of diesel and fertilizer; some are worried they will miss the planting season if supplies aren’t bolstered soon.

The UN has issued stark warnings, including of possible famines, as the Iran war compounds the toll for countries already racing to plug gaps left by the sudden cut of US and European aid. “My biggest worry this year is not even just price, but availability,” a nonprofit worker in Malawi told Bloomberg.