Ethiopia said it must defend itself against an all-out invasion by Eritrean troops this week. Foreign Minister Gedion Timothewos said Eritrean forces deployed 60 km into northern Ethiopia. The government called the presence of these troops a blatant act of aggression. Witnesses also saw soldiers in the region this week.

In the government's first official statement on reported incursions by Eritrean troops ​this week that have raised fears of outright war ​between the Horn of Africa neighbours, Ethiopia's Foreign Minister ⁠Gedion Timothewos said that the Eritrean forces had deployed ​up to 60 km (37 miles) into northern Ethiopia.

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The letter was shared ​with Reuters by a senior Ethiopian government official.

Eritrea’s information minister Yemane Gebremeskel did not immediately respond to a request for comment on Friday. On ​Wednesday he called reports of an Eritrean incursion part ​of an Ethiopian plan to justify a war of aggression against his country.

Ethiopia's letter ‌called ⁠the presence of Eritrean troops on its soil "a blatant act of aggression that engages Ethiopia's inherent right to self-defence."

"Taking its belligerence and intransigence to a whole new level, the Eritrean ​government has deployed ​its troops, ⁠including mechanized units, deep into Ethiopian territory," the letter said. "The all-out invasion of parts of northern ​Ethiopia by Eritrea is a matter of ​public record."

Eritrean soldiers ⁠were seen in northern Ethiopia this week, witnesses told Reuters, days after the neighbours severed diplomatic ties.

Ethiopia has accused Eritrea of backing a ⁠rebel ​alliance battling federal government troops since ​September 23 in the northern regions of Tigray, Amhara and Afar. Eritrea has ​denied this.

Reporting by Reuters bureaus Editing by Silvia Aloisi and Peter Graff