"President Omar al-Bashir has apologised to King Salman of Saudi Arabia for being unable to attend the Riyadh summit," a statement from his office carried by the official SUNA news agency said.
Bashir has evaded arrest since his indictment by the ICC for alleged genocide, war crimes and crimes against humanity related to the 14-year-old conflict in Darfur that has killed tens of thousands.
His planned attendance at Sunday's summit of Arab and Muslim leaders in Riyadh had drawn strong criticism from Washington.