Serious violations are continuing in Ethiopia despite a peace deal in the north, UN rights experts said Monday, warning the conflict was spreading across the country and putting regional stability at risk.

The United Nations-backed investigators cautioned in a statement that "atrocities, war crimes and crimes against humanity are still being committed in the country".

This comes despite the November 2022 peace deal between Ethiopia's federal government and rebels in the Tigray region, which ostensibly ended a devastating two-year conflict.

"While the signing of the agreement may have mostly silenced the guns, it has not resolved the conflict in the north of the country, in particular in Tigray," said Mohamed Chande Othman, head of the UN-backed Commission of Human Rights Experts on Ethiopia.

"Nor has it brought about any comprehensive peace," he told reporters, presenting the commission's latest report.

The report confirmed that Eritrean troops and Amhara militia members were continuing to commit grave violations in Tigray, "including the systematic rape and sexual violence of women and girls", the statement said.

"It is hard to overstate the gravity of the violence, which has taken place in Ethiopia," Othman said.

Equally alarming, the report said, is that "hostilities in Ethiopia are now at a national scale, with significant violations increasing particularly in Amhara region, but also ongoing in Oromia and elsewhere".

In a number of regions, "ongoing patterns of violations, entrenched impunity and increasing securitisation of the state bear hallmarked risks of further atrocities and crimes", Othman said.

The commission said it had uncovered ongoing patterns by government forces of arrest, detention and torture of civilians in Oromia.

And it said it was already receiving numerous credible reports of violations against Amhara civilians since the announcement of a state of emergency last month.

"The risk to the state as well as regional stability and the enjoyment of human rights in East Africa cannot be overstated," the report said.