The UN Security Council has failed to agree on a joint statement on the crisis in Ethiopia's northern Tigray region, after Russia, China and India concluded it was an internal matter.

Diplomats quoted by the AFP news agency said three African nations on the council - Kenya, Niger and Tunisia - had supported a draft statement.

It would have called for immediate humanitarian assistance and a halt to hostilities, while asserting Ethiopia's sovereignty, the agency reports.

The UN High Commissioner for Human Rights had earlier said there were distressing reports of continued violations that may amount to war crimes in Tigray.

Michelle Bachelet highlighted incidents of sexual and gender-based violence, extra-judicial killings and widespread destruction.

The UN rights office wants to be granted access to investigate reports of atrocities carried out by the Ethiopian and Eritrean armed forces, the Tigray People’s Liberation Front and Amhara Regional Forces.