Spain coach Vicente del Bosque on Friday revealed that Chelsea striker Costa will not feature in a Euro 2016 qualifier against Belarus a week on Saturday or the friendly against world champions Germany three days later.
Costa has been struggling with a hamstring injury since arriving at Stamford Bridge and Mourinho last month criticised Del Bosque for playing the big-money signing from Atletico Madrid in both qualifiers against Slovakia and Luxembourg.
Del Bosque stated that the decision to leave Costa out had been made after consultation with Chelsea's medical staff, with both parties agreeing it was the right decision in the long term.
Mourinho also revealed that Costa, who has scored nine goals in eight Premier League games, will start Saturday's clash against Liverpool at Anfield.
"We think he is ready to start the match [on Saturday]," said the former Real Madrid coach.
"In the 15 days [international break] he can rest and work. It is fantastic news for us. I thank the Spain FA for the decision that they made.
"The plan is to have a period of complete rest after the match for a few days, and after that to continue the specific work he is doing without having a match to play on the weekend."
Mourinho also stated that Loic Remy is in contention for the clash at Anfield after recovering from a groin injury.
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