Barcelona and Real Madrid must agree on the date of the Clasico and announce it to the RFEF by Monday 21st October at 10am. If they do not reach it then the competition committee of the RFEF will decide the date.
They confirmed on Friday after an extraordinary meeting that the game would not be going ahead on Sat 26th as planned, or played at the Santiago Bernabeu instead.
December 7th may be a good new date, if the clubs agree on it.