"Deliveries of assistance within Tigray are not matching the needs and WFP and its cooperating partners urgently need access to all parts of the region," the UN food agency said in a statement Friday.
"Since the start of November, WFP has reached 29 percent of its caseload of 2.1 million people with food assistance in the Tigray region," it said.
WFP said an estimated 13.6 million people across Tigray and its neighboring regions of Amhara and Afar were dependent on humanitarian aid as a result of the war, which broke out in November 2020.
Restoring aid deliveries to Tigray was a key part of an agreement signed on November 2 to end a two-year war that has killed untold numbers of people and unleashed a humanitarian crisis.
All four road corridors into Tigray having been reopened since the ceasefire and humanitarian flights were flying into major cities, allowing a significant uptick in aid supplies reaching the region.
Aid into the region ground to a halt in late August when fighting resumed between the Ethiopian government and their allies, and fighters loyal to Tigray's rebellious authorities.
Even before the suspension of aid, the UN had warned many in Tigray already faced starvation, with some 90 percent of its six million people dependent on food assistance.
Tigray's authorities had been resisting central rule for months when Ethiopian Prime Minister Abiy Ahmed accused their leadership of attacking federal army camps and sent troops into the region.
The two parties signed a peace deal in South Africa on November 2 that agreed to unfettered aid into Tigray.