He was on coach Thomas Tuchel's previous list for friendlies against Japan and Uruguay, but as reported by the BBC, he will not travel to the World Cup in North America.
Maguire commented on the coach's decision via Instagram, stating that he was disappointed.
"I was confident that I could play an important role for my country this summer after the season I had. I am shocked and devastated by this decision. I wish the players all the best," the Manchester United footballer wrote.
Tuchel is scheduled to reveal the tickets for the World Cup, which begins on June 11, on Friday.