The World Food Program has started distributing food aid in Ethiopia's war-scarred Tigray region in a test of new monitoring measures, the United Nations agency said on Tuesday.

WFP and U.S. aid agency USAID halted food aid to Africa's second-most populous country in June after discovering that supplies were not reaching those in need, raising fears that millions of Ethiopians would be left in desperate straits.

On Tuesday, the U.N. food agency said it had "started distributing 15-kilogram (33-pound) pre-packed bags of wheat to just over 100,000 people" as part of a pilot project with improved monitoring mechanisms.

"On July 31, the World Food Program started testing and verifying enhanced controls and measures for delivering food assistance in four districts of Tigray," it said in a message to AFP.

The new measures include tracking supplies and the digital registration of recipients to prevent aid from falling into the wrong hands.

Millions of Ethiopians are facing severe food shortages following a brutal two-year war in Tigray as well as a punishing drought that has also struck Somalia and parts of Kenya.

A spokesperson for USAID, the U.S. government's main international aid agency, told AFP that U.S. food assistance in Ethiopia remains paused.

"We are committed to resuming food assistance as quickly as possible once we can be confident our assistance is reaching the most vulnerable that it is intended for," the spokesperson said.

The Amhara region, which neighbors Tigray, has also witnessed clashes between a local militia and the national army in recent weeks, affecting humanitarian operations there, according to the World Health Organization.

"WFP also plans to begin registering populations and rolling out the new enhanced control measures for targeted, vulnerable people in Amhara, Afar and Somali regions, as well as other parts of Tigray region, as soon as possible," the agency said.

The escalation in violence in Amhara prompted Prime Minister Abiy Ahmed's government to declare a six-month state of emergency there last week.

On Tuesday, Ethiopian Airlines canceled flights to Bahir Dar, the capital of Amhara, because of the clashes. Last week, the airline canceled flights to three other airports in the northern region.

The fresh unrest comes nine months after the end of the war in Tigray, which drew in fighters from Amhara.

Tensions have been rising since April, when the federal government announced it was dismantling regional forces across Ethiopia.