UN Secretary General Ban Ki-moon has arrived in South Sudan in a bid to demand the involving sides of the conflict end the four-month-old clashes in the country.

A UN statement released on Tuesday upon his arrival in the capital, Juba, read, “The Secretary-General has repeatedly called on the leaders to find a political solution, and to put an immediate end to the violence which has led to the suffering of so many innocent civilians.”

South Sudan has been witnessing violence since December 2013, when political rivalry between President Salva Kiir and his former vice president, Riek Machar, turned violent.

The conflict soon turned into an all-out war between troops backing Kiir and defectors loyal to Machar, with the violence taking on ethnic overtones that pitted the Nuer people aligned with Machar against the Dinka, who support Kiir.

Thousands of people have so far been killed and more than one million displaced in the conflict.

The UN has repeatedly warned that the violence could turn into genocide.