Fikayo Tomori is aware "I have to do more" to avoid a repeat of the "disappointment" at being left out of England's World Cup squad.
Despite playing every match for Milan in Serie A this season, while missing just one of their six Champions League games through suspension, the defender was not included by Gareth Southgate, whose side were eliminated by France in the quarter-finals.
Tomori also played a key role as the Rossoneri last term, featuring 31 times as they ended their 11-year wait to claim the Scudetto, pipping rivals Inter to the title on the final day of the campaign.
But having only earned three senior England caps since making his debut against Kosovo in November 2019, the 24-year-old feels he must raise his game to force himself back into contention for the European Championship in 18 months' time, should the Three Lions qualify.
"I'm always motivated, obviously there is disappointment because I wanted to be there," he told DAZN. "But it didn't happen, and I know I have to do more to go to Euro 2024.
"There was disappointment, but I have to keep working and then let's see. Right now, I'm happy and content."
Tomori and Milan resume their Serie A title defence when they travel to Salernitana on January 4. Stefano Pioli's side are second after 15 matches, but already trailing unbeaten leaders Napoli by eight points.
The centre-half admits the reigning champions have had to adapt to different challenges from their opponents this season, but he is confident the campaign can culminate in a successful title defence.
"In my opinion, the most difficult thing is to win again," he added. "Last year, we know that there weren't many people who thought we could win. But now we have done it, and we have the Scudetto on our chest, whoever plays against us changes.
"So, we have to look for another way to win and another level - both in mentality and in play. We knew it would be difficult, but we can win again, and we will do everything for that."