United called time on Mourinhos reign on Tuesday with the 55-year-old informed of the decision by executive vice-chairman Ed Woodward at the clubs training ground.
Mourinhos final game in charge was the 3-1 defeat to Liverpool on Sunday, which has left United 19 points behind Jurgen Klopps side and in serious danger of missing out on a place in next seasons Champions League.
Guardiola, however, has sent his best wishes to Mourinho and has hailed the Portugueses strong character.
I am always sad for the manager when that happens, Guardiola told Sky Sports.
We are alone in that situation. I am close to all of the managers.
You are sacked when results are not good.
He doesnt need me, he is so strong.
I wish him all the best and he will be back soon.
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