United Nations, January 26 (RHC)-- The United Nations is calling on African Union states to help pull South Sudan's parties out of a deadlock in the country's peace process.

UN Secretary General Ban Ki-moon said African Union states should address South Sudan's failure to meet a Friday deadline to establish a transitional government of national unity.

Forming a transitional government is an "essential step" in implementing the peace deal between South Sudan's government and rebels, said Ban Ki-moon through his spokesman on Monday.

Ban advised both of South Sudan's warring sides to overcome their differences, asking African leaders to place the issue of South Sudan at the top of the agenda at the AU summit this week. And the UN chief confirmed he would personally attend the upcoming African Union summit.