Jack Grealish says being left out of England's Euro 2024 squad was the "most difficult thing I have had to deal with in my career".

The Manchester City forward, 28, said he was "heartbroken" but is determined to use the experience as motivation going forward.

Grealish came on as a substitute in England's 3-0 warm-up win against Bosnia-Herzegovina at St James' Park just over a week before the tournament started, but was not included in Gareth Southgate's final 26-man squad.

England would go on to reach the final, which they lost 2-1 to Spain.

"When you are on your holidays, every time you turn on the phone or the TV you just see it [the tournament], so it was hard not to see," added the former Aston Villa player, who has 36 England caps.

"I'll be honest, football-wise it was the most difficult thing I've ever had to deal with in terms of my own career.

"I was absolutely heartbroken. For myself now moving forward, I have to just try and use that as motivation going into this season."

Grealish cost City a British record £100m when he joined City from Villa in August 2021, one month after featuring for England in the Euro 2020 final against Italy.

"I felt I should have been in the [England] squad," added Grealish, who was speaking on City's pre-season tour of the United States.

"I feel like I offer something different to players in the England squad.

"But it is what it is.

"As I said, it was the hardest moment for me as a footballer. I've had a lot of ups and downs in my career."