Manchester City chairman Khaldoon Al Mubarak says he holds no grudges against Uefa.
European football's governing body gave City a two-year ban from their club competitions in February for "serious breaches" of Financial Fair Play regulations.
That ban was overturned by the Court of Arbitration for Sport last month.
Boss Pep Guardiola said in July City deserved an apology, but Khaldoon said: "Life is too short to carry grudges."
Speaking to club media, he added: "It is one of the most prestigious competitions in the world of sports and it is a competition we want to win and it is a competition we have to respect in order to win.
"And this was a challenge, it's behind us, end of story. I am focused on one thing: how I can help this club compete in this competition and win it and how to have a constructive relationship with Uefa. I think it's the only way to go."
- City target more transfer signings
City's hopes of winning the Champions League this year were ended by Lyon who beat them 3-1 in the quarter-finals, while they finished second in the Premier League, 18 points behind champions Liverpool.
Guardiola has already started strengthening his side for a renewed assault on both the Premier League and the Champions League next season, which begins this weekend with the traditional curtain-raiser - the Community Shield.
Defender Nathan Ake has joined from Bournemouth for £40m while winger Ferran Torres arrived from Valencia at the start of August for £20.87m.
Guardiola is keen to bring in a right-sided central defender, with Napoli's Kalidou Koulibaly a player the club is keen on, although no official bid has been made yet.
Khaldoon said there will be more arrivals at Etihad Stadium this summer.
He added: "We don't take a one-year view, we take a three, five, 10 year-view and when we look at what changes or improvements we have to make for this squad, we are going to make them.
"We'll be sensible and pragmatic about it but we will do what it takes, I think you've seen when it comes to the two acquisitions we have made, Ake and Ferran Torres, we moved quickly.
"There are additional players we will be bringing in and we will stick to the plan, obviously within the realities of the market that we live in today."