Eritrean authorities have suspended all flights by Ethiopian Airlines to the East African nation effective Sept. 30, the airline said on Wednesday.

Flights from Ethiopia to Eritrea had resumed in 2018 after two decades, following a peace deal between the two neighbours that earned Ethiopia's Prime Minister Abiy Ahmed a Nobel peace prize a year later.

"Ethiopian Airlines has received a notice from the Eritrean Civil Aviation Authority through a letter... indicating the suspension of all Ethiopian Airlines flights to Eritrea, effective September 30, 2024," the airline said in a statement posted on its official Facebook page.

"The specific reasons for this suspension have not been disclosed to us," it said.

Eritrea Information Minister Yemane Gebremeskel did not immediately respond to a request for comment.

Hanna Atnafu, a spokesperson for the airline, told Reuters the flight suspension came as a surprise.

"What is shocking and saddening to our airlines was just 15 days ago, on July 8, there was a letter sent to (us) requesting, to increase our weekly flight frequency from 10 flights to 15," Hanna said.

State-owned Ethiopian Airlines is ranked the largest in Africa by revenue and profit by the global industry body International Air Transport Association.