CAIRO – Egypt retaliated against Ethiopia on Thursday by declaring an Ethiopian diplomat persona non grata and ordering him to leave within 48 hours, as a deepening crisis between Ethiopia and Eritrea raised fears of a wider regional conflict.

The move followed Ethiopia’s expulsion of an Egyptian diplomat in Addis Ababa, with Cairo saying it regretted the decision and firmly rejected any suggestion that it interfered in Ethiopia’s internal affairs.

Under the principle of reciprocity, Egypt declared Egazi Emelo Borougi, a counsellor at the Ethiopian Embassy in Cairo, persona non grata and gave him 48 hours to leave the country, Egypt’s state news agency MENA reported.

A senior Egyptian official told MENA that Cairo maintained a policy of refraining from commenting on domestic developments in Ethiopia and elsewhere, in accordance with international law and the UN Charter.

“The Ethiopian side has a history of attributing its failures in managing its internal affairs and its successive crises to alleged foreign interference, thereby concealing its ongoing problems,” the official said.

The diplomatic dispute came as Ethiopia and Eritrea moved sharply towards confrontation, with Addis Ababa announcing the closure of its embassy in Asmara and the expulsion of 10 Eritrean diplomats. Eritrea responded by severing diplomatic ties with Ethiopia.

The escalation followed overnight explosions heard in Addis Ababa and renewed fighting in northern Ethiopia, raising concerns that the conflict could spread beyond the country's front lines.

Ethiopia has accused Eritrea, Sudan and Egypt of supporting an opposition alliance led by the Tigray People’s Liberation Front (TPLF), which has been battling forces loyal to Prime Minister Abiy Ahmed’s federal government since last week. Egypt, Eritrea and Sudan deny the accusations.

The African Union Commission urged Ethiopia, Eritrea and Egypt to exercise maximum restraint and refrain from actions or statements that could worsen tensions and undermine regional peace and stability.

“The Commission urges the three countries to address their differences through established diplomatic channels and peaceful dialogue,” it said in a statement late on Thursday.

Ethiopia said its decision to close its embassy in Asmara was in response to what it called Eritrea’s “direct and indirect acts of hostility and belligerence against Ethiopia”. It said the 10 Eritrean diplomats, whose names were not disclosed, must leave within 48 hours.

Eritrea’s Information Minister Yemane Gebremeskel said that expelling all Eritrean diplomats from Ethiopia effectively amounted to closing Ethiopia’s embassy in Asmara. Eritrea’s foreign ministry said the country had “no option but to reciprocate in kind” and sever diplomatic ties with Ethiopia.

A source linked to the opposition alliance said that it had carried out several drone strikes in the capital, including attacks targeting military headquarters. If confirmed, the strikes would be the first known drone attacks by anti-government forces on Addis Ababa, hundreds of kilometres from the front lines in Tigray, Amhara and Afar.

Three diplomatic sources confirmed the blasts, speaking on condition of anonymity because of the sensitivity of the matter. Witnesses said there was no visible damage near the military base.

Spokespeople for Abiy’s office, the federal government, the Ethiopian National Defence Force and the TPLF did not respond to requests for comment.

The escalation marks the biggest outbreak of fighting in Ethiopia since the end of the 2020-2022 civil war, in which hundreds of thousands of people were killed. Eritrea fought alongside Ethiopia’s federal forces during that conflict.

The two countries had moved closer after Abiy reopened Ethiopia’s embassy in Eritrea in 2018 as part of a rapprochement that earned him the Nobel Peace Prize. Their militaries later fought together against the TPLF, but Eritrea was excluded from the peace agreement that ended the war in November 2022 and relations soon deteriorated.

The two governments have also clashed over Ethiopia’s efforts to secure access to the Red Sea. Landlocked Ethiopia says access to the sea is vital to its security and economy, while Eritrea has said it fears Addis Ababa could seek to take control of its Assab port by force.

Days after the latest clashes began, the chief administrator of the northern Afar region, Haji Awol Arba, told Al Jazeera that Eritrean soldiers had crossed into Afar to join the opposition alliance’s offensive. Eritrea’s information minister did not immediately respond to a request for comment.

Federal troops and allied militiamen meanwhile made fresh gains in Tigray and Afar, according to a pro-government militia, although Reuters could not independently verify the claims.

Ethiopia’s national intelligence service has banned drone flights over Addis Ababa as concern grows over the opposition’s potential access to armed drones. Opposition forces had not previously been known to use such weapons, but evidence has emerged that they may possess some capability.

On Tuesday, the pro-government Tigray Peace Forces said it had captured drone frames and batteries from forces linked to the TPLF.

Edward Bach, senior Africa analyst at risk intelligence company Verisk Maplecroft, said the opposition’s ability to strike Addis Ababa would be “a political game-changer”, potentially undermining the government’s narrative that the capital remains unaffected by the war and reducing the tactical advantage provided by federal forces’ air superiority.

Federal forces have been advancing in southern Tigray towards the regional capital Mekelle, while the opposition alliance has captured towns in neighbouring Afar.

The Tigray Peace Forces said pro-government forces had also recaptured Erbeti in Afar, which TPLF forces seized at the start of the conflict, thanking the Ethiopian National Defence Force for what it described as “magnificent air support”.

In Afar, where the TPLF captured several towns in the early days of the conflict, fighting has forced tens of thousands of people to flee their homes, Valerie Browning, founder of the Afar Pastoralist Development Association, said.