England forward Mason Greenwood says he "only has himself to blame" after being dropped from the squad over a breach of Covid-19 guidelines in Iceland.
Both players had made their senior international debuts in Saturday's 1-0 Nations League victory in Reykyavik.
Greenwood said: "I can only apologise for the embarrassment I have caused."
He added: "In particular, I want to apologise to Gareth Southgate, for letting him down, when he had shown great trust in me."
"Playing for England was one of the proudest moments in my life and I only have myself to blame for this huge mistake.
"I promise my family, the fans, Manchester United and England that this is a lesson I will learn from."
In a social media post on Monday, Foden said missing England's next match on Tuesday, against Denmark in the Nations League, "hurts" and he will "learn a valuable lesson from this error in judgement".
"I made a poor decision and and my behaviour didn't meet the standards expected of me," he wrote.
"I apologise to Gareth Southgate, to my England team-mates, to the staff, supporters and also to my club and my family."
A Reykjavik Metropolitan Police spokesperson told BBC Sport that Greenwood and Foden were both fined 250,000 Icelandic krona (£1,360).
Southgate confirms Foden and Greenwood will leave the England camp after breaching coronavirus guidelinesMore to follow.
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