UNITED NATIONS (AP) — The United Nations food agency said Tuesday it is stopping food distribution in areas of war-torn Yemen controlled by the Houthi rebels, a move that will impact millions of people.

The World Food Program said the “pause” was driven by limited funding and the lack of agreement with the rebel authorities on downscaling the program to match the agency’s resources.

“This difficult decision, made in consultation with donors, comes after nearly a year of negotiations, during which no agreement was reached to reduce the number of people served from 9.5 million to 6.5 million,” WFP said in a statement.

U.N. spokesman Stephane Dujarric said WFP has tried unsuccessfully “to establish a system that is safe and accountable for the aid going through” to the rebel-held areas.

The war in Yemen has raged for eight years between the Iran-backed Houthis and pro-government forces, backed by a coalition of Gulf Arab states. The Houthis swept down from the mountains in 2014, seized much of northern Yemen and the country’s capital, Sanaa, and forced the internationally recognized government to flee into exile to Saudi Arabia. Since then, more than 150,000 people have been killed by the violence and 3 million have been displaced.

The WFP announcement came as the Houthis have unleashed attacks on ships in the Red Sea, imperiling traffic along one of the world’s most vital shipping lanes, critical to global trade. The Houthis support the Palestinian militant Hamas group and the attacks are linked to the ongoing Israeli-Hamas war.

WFP said food stocks in Houthi-controlled areas “are now almost completely depleted and resuming food assistance, even with an immediate agreement, could take up to as long as four months due to the disruption of the supply chain.”

The Rome-based U.N. agency said it will continue its other programs, such as nutrition and school feeding projects, to limit the impact of the pause in food distributions. In government-controlled areas of Yemen, WFP said general food distribution will continue “with a heightened focus on the most vulnerable families.”

“Similar prioritization is taking place in nearly half of WFP’s operations around the world as the agency navigates the challenging financial landscape that the entire humanitarian sector is facing,” the agency said.

At the end of October, WFP and the U.N. Food and Agriculture Organization warned that acute food insecurity is likely to deteriorate further in Yemen through April 2024. It called for urgent and scaled-up assistance to Yemen and 17 other “hunger hotspots” to protect livelihoods and increase access to food.