Flick, whose current deal was due to expire in June 2027, is set to sign a one-year extension, with an option to prolong his tenure. His team moved to an unassailable 91 points with three games remaining, securing the title by beating arch-rivals Real Madrid.
"I'll let you know - sorry - the last few days I’ve had different things to do," Flick, whose father died on Sunday, told reporters.
"Of course, I'm really happy about this (contract extension). They have given me and my team the confidence to work one or two years more, so for me it's like that.
"I think a lot of coaches would be happy if they get a contract of three, four or five years, but in Barca's case it's good to limit it. I really appreciate it a lot.
"We go to 2028 and then we'll see if everything is right, and if so, we can decide on one more year. The club has the right, and I have the right - I think it's a good deal."
The 61-year-old German, a treble-winning coach with Bayern Munich, joined Barca in 2024 on a two-year deal. He arrived eager to redeem himself after being sacked by Germany in September 2023.
Under Flick, Barca quickly reasserted their domestic dominance, winning back-to-back LaLiga titles along with the 2024/25 Copa del Rey and successive Spanish Super Cup trophies.
However, they were knocked out of this season's Champions League by Atletico Madrid at the quarter-final stage.
"In the last few days they showed me that I am here in the right place, and I really appreciate what they give me - all the people, to me and my team, and my family," he said.
"For next season, it is also a big commitment for us to work harder, even harder than this season, to reach the best level with the team and to win titles.
"This is normal for Barca. I know everyone has this dream to win the Champions League. We will try again. That's what I can say. I am grateful for the confidence they have given me to work here for more years."
Barca face Deportivo Alaves on Wednesday.