Philippe Coutinho confirmed Liverpool did everything in their power to keep him at Anfield, but says his move to Barcelona is a "dream come true".
The Brazil international signed a five-and-a-half-year deal with Barcelona on Monday after completing his £146m move from Liverpool.
Liverpool rejected repeated bids from Barcelona in August for Coutinho, but the clubs reached an agreement this weekend.
"I just want to thank the club for its patience and its effort," Coutinho said. "I'm very happy, this is a dream come true for me and I hope to live up to the expectations."
Coutinho is also grateful to Liverpool for allowing him to realise his dream of playing for Barca.
"They understood that it was what I wanted," Coutinho said. "They did all they could to try to keep me, but in the end they understood that it was my dream, and the dream of my family, to come here.
"I just would like to thank all the fans, all the staff and all the players for the years I lived there.
"For sure, I gave everything I could. Unfortunately we could not win but I lived [in Liverpool] for five years and my family was very happy there. So I just would like to thank them and wish them all the best."
Coutinho cannot play for Barcelona in the Champions League for the rest of the season because he has already played for Liverpool in the competition this campaign, and will have to wait around three weeks to make his debut after sustaining a thigh injury.
"I won't be able to play some matches now, but it's a five-year contract, so I'll have plenty of time to help the club in the future," he said. "Sometimes you don't get another opportunity like this, to join Barcelona, so I didn't think twice."
The move to Catalonia will see Coutinho reunite with former Liverpool team-mate Luis Suarez and he revealed the Uruguayan helped convince him to leave Anfield for Barcelona.
"We almost won the Premier League together at Liverpool, it was a great time," Coutinho said.
"We are good friends and he wrote me a lot of messages telling me about the city and the club. It just made me want to come here even more."
Barcelona has now reinvested the £198m (€222m) windfall it received from PSG following Neymar's transfer after also buying Ousmane Dembele from Borussia Dortmund in the summer.
Coutinho will be the latest in a long line of Brazilians to light up the Nou Camp but he is keen to avoid comparisons with his predecessors.
When asked about Neymar, Coutinho said: "He is a great player, but we have different characteristics. I'm here to try to gain my space in the team."