In this March 16, 2015, file photo, U.N. Secretary General Ban Ki-moon delivers a speech during a symposium of the 70th anniversary of the United Nations at the U.N. University in Tokyo.

U.N. Secretary-General Ban Ki-moon has appointed the heads of four working groups on Syria, the United Nations said on Tuesday, signalling a step towards talks where warring parties are expected to discuss how to implement a roadmap for peace.

“It is hoped that their outcomes could eventually set the stage for a Syrian agreement to end the conflict on the basis of the Geneva Communique,” U.N. Syria envoy Staffan de Mistura said in a statement, referring to a 2012 international agreement on resolving the war.

The four are Jan Egeland, Nicolas Michel, Volker Perthes and Birgitta Holst Alani, de Mistura’s office said.