"Today, we received a notice from [UN's Syria envoy] de Mistura's office that the next round of negotiations would begin in Geneva on April 13 instead of 11," the source said.
The previous round of Syrian talks wrapped up on March 24 after 10 days of intense discussions.
"A few days ago we received a written notice from de Mistura's office that the round would begin on the 11th, but this morning we were informed that it had been postponed," the source added.
By the end of the previous round of talks on Syria's reconciliation, delegates submitted their proposals on how to stop the conflict to de Mistura who then produced a final paper with points of convergence.
The Syrian government’s delegation is anticipated to come to Geneva on April 14, according to Vitaly Naumkin, Russia’s moderator at the Syrian proximity talks in the Swiss city and de Mistura's adviser.