Atletico Madrid coach Diego Simeone said it made “no sense” for matches to go ahead at the weekend, and Barcelona’s Hansi Flick said he would have restricted them.
The real host, AC Milan, in the team stage of the Champions League on Tuesday.
Ancelotti won eight trophies, including two Champions League titles, as Milan coach from 2001 to 2009.
His Real team lost 4-0 to Barcelona on October 26, and two days later, Real striker Vinicius Jr finished second behind Rodri in the fight for the Ballon d’Or.
Since then, the issue of football has been firmly established in the spotlight through the Valencia tragedy.
“It was supposed to be a special match for me against Milan. But now there is no point in talking about football,” Ancelotti said.
“It has been a difficult week, not because of what happened with the Ballon d’Or or the Classic. It happened and that’s it, congratulations to the winners.
“Our disappointment is not because of that. It is because of what is happening here in Spain.”
UEFA has announced that a moment of silence will be observed at all Champions League, Europa League and Conference League matches this week in memory of the flood victims.
In some parts of the Valencia region, a year’s worth of rain has fallen.
On Sunday, Spain’s kings were pelted with mud and other objects by angry protesters during a visit to the city of Paiporta, one of the worst affected in Valencia.
Objects were also thrown at the President of the Government, Pedro Sánchez, who was quickly evacuated from the area.
Barcelona suffered flooding on Monday after torrential rains.
More than 60 flights at El Prat airport have been restricted, delayed or diverted and rail services have been suspended.
