In this file photo, Ethiopia s Prime Minister Abiy Ahmed speaks at a stadium in the town of Jimma in the southwestern Oromia region of Ethiopia, June 16 2021. AP
"It has become necessary to declare a state of emergency as a situation has emerged where it has become difficult to control this unacceptable movement under current law," it said in a statement posted on social media.
The statement did not make clear if the state of emergency applied nationwide or just to Amhara, which lies to the north of the capital Addis Ababa.
Abiy's government did not reply immediately to questions from AFP.
Clashes in Amhara between the national army and local fighters have escalated in recent weeks, prompting travel warnings from foreign governments and the cancellation of flights by the national carrier Ethiopian Airlines.
Tensions have been rising since April when the federal government announced it was dismantling regional forces including in Amhara, where nationalists felt the move would weaken Ethiopia's second most populous region.
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