The games against Brazil at Wembley on Saturday and Belgium at the same venue next Tuesday are England’s last outings before Southgate announces his Euro squad in May.
Saka’s withdrawal comes as Arsenal prepare for a dramatic end to the season.
The Gunners sit top of the Premier League and face a Champions League quarter-final clash with Bayern Munich.
“Bukayo Saka has left the England camp and returned to his club for continued rehabilitation,” a Football Association statement said on Thursday.
“The Arsenal forward reported to St George’s Park with an injury and has been unable to participate in training.
“No further replacements are planned as a 25-man England squad continue their preparation for the forthcoming internationals with Brazil and Belgium.”
Prior to leaving the squad, Saka had been working indoors on an individual programme along with Harry Kane, Cole Palmer and Jordan Henderson.
© Agence France-Presse
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