"The Prime Minister said he tried his utmost effort to solve the crisis in his country and he is resigning now to be part of a solution to it", Fana reported.
A 10-month national state of emergency that ended past year failed to stop the protests, as did the release of thousands of opposition supporters from jail last month.
Beyond the political reality in Ethiopia, Desalegn came to power at a time when Ethiopia's economy was starting to grow.
But whatever it is labelled, Ethiopian Prime Minister Hailemariam Desalegn's surprise resignation is setting the stage for a crucial succession race, that is likely to shape the future course of a country rocked by violent unrest and political instability.
In recent months, internal political wrangling between four coalition partners of EPRDF, Tigray Peoples Liberation Front (TPLF), Amhara National Democratic Movement (ANDM), South Ethiopia People's Democratic Movement and Oromo Peoples Democratic Organization (OPDO) has cast fears over the stability of the nation of about 100 million people.
Ethiopian People's Revolutionary Democratic party has been ruling the country for the last quarter of a century after the regime of Colonel Mengistu Hailemariam, who is in exile in Zimbabwe. Discord and turmoil escalated in 2015 and 2016 as protests aimed at human rights abuses and political restrictions increased, according to Al Jazeera.
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After a few minutes, she was seen sitting under her own power, and was soon walking without assistance, albeit gingerly. Sweeney, 24, is competing in her first Olympics after missing out on a spot in the 2014 Winter Games in Sochi, Russia.
The government responded with deadly force, imposed an emergency rule, banned the posting of updates on Facebook, repeatedly blocked the internet, and declared that watching opposition, diaspora-run television stations illegal.
The BBC's Emmanuel Igunza, in the capital Addis Ababa, says the government has released thousands of opposition supporters from jail, but the protests have continued.
However, the resignation did not necessarily mean reforms would stop, the analyst said.
Desalegn confirmed that he will remain as prime minister but only in a caretaker capacity.