South Sudan’s President Salva Kiir and his former deputy Riek Machar have signed a deal to end the hostilities that have left thousands of people dead in the African country.

On the invitation of Tanzanian President Jakaya Kikwete, Kiir and his arch-rival, Machar, held talks in the northern Tanzanian town of Arusha on Monday.

The two sides accepted responsibility for South Sudan’s 10-month-old civil war.

“The parties acknowledge a collective responsibility for the crisis in South Sudan that has taken a great toll on the lives and property of our people,” read the text of the agreement.

Both sides stressed that the divided ruling party, the Sudan People’s Liberation Movement (SPLM), should be reunited.

“A divided SPLM will automatically fragment the country along ethnic and regional fault lines,” the deal read, urging “genuine and honest dialogue that puts the interest of the people and the nation above all.”

The peace talks, which were organized to find a lasting solution to the conflict in South Sudan, had repeatedly broken down.

South Sudan plunged into violence in December 2013, when fighting erupted between troops loyal to the president and defectors led by Machar around the capital, Juba.

The conflict soon turned into an all-out war between the army and defectors, with the violence taking on an ethnic dimension that pitted the president’s Dinka tribe against Machar’s Nuer ethnic group. The clashes have left thousands of South Sudanese people dead and forced around two million others to flee homes in the world’s youngest nation.

South Sudan gained independence in July 2011 after its people overwhelmingly voted in a referendum for a split from Sudan.