Ethiopian Prime Minister Abiy Ahmed has for the first time acknowledged that Eritrean troops have been involved in the fighting in the northern province of Tigray.

It had been months since the two countries denied that the troops had crossed the border.

Addressing the Ethiopian parliament, Abiy said he had spoken to the Eritrean authorities about the allegations that the Eritrean forces had committed atrocities in Tigray.

He did not allow Eritrean troops to enter Ethiopian cities, where human rights groups say they have committed atrocities, including the killing of civilians (unarmed civilians).

• Thousands of Ethiopians have lost their homes since the war began in November.

For many observers of the situation in the country, it has long been clear that Abiy has made an agreement with the Eritrean president to work together to oust the enemy they have in common – the Tigray state government.

In a wide-ranging speech to parliament, Abiy said on Tuesday Eritrean troops had crossed the border and entered the region because they were concerned they would be attacked by the longtime foe – the TPLF, which dominated Ethiopian politics for decades until Abiy came to power in 2018, had presided over a brutal 1998-2000 war with Eritrea.

Abiy said Eritreans had promised to leave when Ethiopia’s military was able to control the border.

He added that the “Eritrean people and government did a lasting favour to our soldiers”, during the conflict, without giving more details.

“However, after the Eritrean army crossed the border and was operating in Ethiopia, any damage it did to our people was unacceptable,” he said.

“We don’t accept it because it is the Eritrean army, and we would not accept it if it were our soldiers. The military campaign was against our clearly targeted enemies, not against the people. We have discussed this four or five times with the Eritrean government

‘War narrative’

The comments also marked the first time Abiy appeared to acknowledge that serious crimes have taken place in Tigray, home to six million people.

“Reports indicate that atrocities have been committed in Tigray region,” Abiy said.

War is “a nasty thing”, he added, speaking the local Amharic language. “We know the destruction this war has caused.”

After months of tension, fighting erupted in Tigray after forces loyal to the TPLF – whose leaders challenged Abiy’s legitimacy after the postponement of elections last year – attacked army bases across the region overnight and in the early hours of November 4.

The attacks initially overwhelmed the federal military, which later launched a counteroffensive alongside Eritrean soldiers and forces from the neighbouring region of Amhara. The federal army is now hunting the fugitive TPLF leadership.

Abiy said soldiers who raped women or committed other war crimes will be held responsible, even though he cited “propaganda of exaggeration”.

He spoke as concerns continue to grow over the humanitarian situation in the embattled region.

Abiy accused the TPLF’s leaders of drumming “a war narrative” while the area faced challenges such as a destructive invasion of locusts and the COVID-19 pandemic.

“This was misplaced and untimely arrogance,” he said.

The Ethiopian prime minister, who won the Nobel Peace Prize in 2019 for his efforts to make peace with Eritrea, faces pressure to end the conflict in Tigray as well as to institute an international investigation into alleged war crimes.

The government’s critics say a continuing federal inquiry is not enough because the government cannot effectively investigate itself.

On Monday, the heads of nine UN agencies and other officials demanded a halt to attacks against civilians in Tigray, “including rape and other horrific forms of sexual violence”.

In a joint statement, the UN agencies, the UN special investigator on the human rights of internally displaced people, and two umbrella organisations representing NGOs also called on all parties in Tigray to explicitly condemn all sexual violence and ensure their forces “respect and protect civilian populations, particularly women and children, from all human rights abuses”.

UN deputy spokesman Farhan Haq said on Monday the conflict continues to drive massive displacement, with tens of thousands of people arriving into Shire, Axum and Adwa, most fleeing fighting in western Tigray in the last few weeks.

There are also reports of people uprooted by violence in the northwest and central areas, he said.

Earlier this month, Human Rights Watch reported that Eritrean forces shot dead hundreds of children and civilians in a November massacre in Tigray.

An Amnesty International investigation into the same events detailed how Eritrean troops “went on a rampage and systematically killed hundreds of civilians in cold blood”.

UN Secretary-General Antonio Guterres joined calls for the Eritrean troops to leave Tigray while the UN human rights chief, Michelle Bachelet, urged an investigation into the situation.