West Ham defensive-midfielder Declan Rice announced on Wednesday that he intends to continue his international career with England after having previously played for Ireland.
Rice, 20, was capped three times by Ireland, but all of his appearances were in friendlies, which allows him to swap his international allegiance to the country of his birth.
With Irish heritage but born in London, Rice says he considers himself "to be of mixed nationality."
Rice, who has made 59 appearances for West Ham, has excelled this season at London Stadium and has attracted England boss Gareth Southgate's attention.
"This has been an extremely difficult decision and, in all honesty, not one I ever expected to be making at this stage of my career," Rice said in a statement.
"In recent weeks and months, I have discussed the situation with the people who mean the most to me. My parents, my family, my girlfriend and my closest friends.
"I have also spoken to Martin O'Neill, Mick McCarthy, Gareth Southgate and to friends and colleagues within the game whose opinion I respect. I am truly grateful for the support I have received leading to this decision."
The news comes a setback for McCarthy, who returned for his second spell as Ireland manager after the departure of O'Neill in November.
"Declan rang me today and said he has decided to give it a go with England. Good luck to him," McCarthy said.
Rice said: "My pride at wearing the Irish shirt was always 100 percent genuine," but added that he hopes to be called up by England because that's "best for my future."
England reached the semifinals at last year's World Cup and will play in the UEFA Nations League final four in June.
Information from Reuters and the Associated Press was used in this story.