A senior UN official has warned the Security Council that urgent measures are needed to avoid famine in the war-torn region of Tigray in Ethiopia, in a briefing seen by AFP.

"There is a serious risk of famine if assistance is not scaled up in the next two months," wrote Mark Lowcock, the UN Under-Secretary-General for Humanitarian Affairs and Emergency Relief Coordinator.

Prime Minister Abiy Ahmed sent troops into Tigray in early November to disarm and detain leaders of the regional ruling party, the Tigray People's Liberation Front (TPLF).

He said the move came in response to TPLF attacks on federal army camps.

More than six months later, Lowcock said, the fighting and abuses continue in Tigray, where the spectre of a famine has been hovering for several months.

"Concrete measures are urgently needed to break the vicious cycle between armed conflict, violence and food insecurity," Lowcock said in his two-and-a-half page note Tuesday.

"I urge members of the Security Council and other Member States to take any steps possible to prevent a famine from occurring," he said.

"Today, at least 20 percent of the population in that area face emergency food insecurity," he said, adding that "destruction and violence against civilians continue even now across Tigray."

"In the six and a half months since the start of the conflict in Tigray in early November 2020 an estimated two million people have been displaced. Civilians are being killed and injured," he added.

"Rape and other forms of abhorrent sexual violence are widespread and systematic. Public and private infrastructure and objects indispensable to the survival of civilians have been destroyed, including hospitals and agricultural land," he warned.

The UN official estimated that "over 90 per cent of the harvest was lost due to looting, burning, or other destruction, and that 80 per cent of the livestock in the region were looted or slaughtered."

Government blames TPLF

"Despite improvements in March and the cooperation of authorities at the local level, humanitarian access on the whole has recently deteriorated," Lowcock wrote.

"Humanitarian operations are being attacked, obstructed or delayed in delivering life-saving assistance. Eight aid workers have been killed in Tigray in the last six months."

Abiy's government has said it is committed to investigating human rights abuses and that it has granted "full and unhindered" access for aid workers. 

In a series of Twitter posts Tuesday night, the foreign ministry blamed the TPLF in part for aid disruptions.

"Remnants" of the group have "killed humanitarian workers, truck drivers & looted food & non-food items that were about to be delivered to the people who need support," it said.

The ministry also said the government had covered the bulk of food assistance delivery "but it still is a subject of attack by some corners who have been reluctant to deliver concrete support."