Hansi Flick pledged Barcelona will learn from their Champions League semi-final elimination at the hands of Inter and come back stronger in the future.

Barca were on the brink of reaching their first European showpiece for a decade after staging an improbable comeback in Tuesday's second leg at San Siro, only for substitute Davide Frattesi to hit the winner for Inter in extra time.

Having trailed 2-0, Barca roared back to lead 3-2 through goals from Eric Garcia, Dani Olmo and Raphinha, while Lamine Yamal hit the post in the dying stages.

But Francesco Acerbi made it 3-3 on the night and 6-6 on aggregate in stoppage time, and Inter came on strong in the additional period, progressing through Frattesi's left-footed winner.

Barca had been chasing a treble after winning the Copa del Rey last month, but they will now turn their focus to LaLiga, where they sit four points clear of Real Madrid with four games remaining.

Unbeaten domestically since late December, Barcelona will try to grab a fourth consecutive victory over Madrid on Sunday, when they have the chance to close in on the title.

"We'll learn from this. It's a progression. We want to keep learning. We don't have much time to train now, but next weekend we are back. It's normal to be disappointed," Flick said.

"The team deserves the respect they have earned. We play to win, we want to win titles and we have LaLiga, with a very difficult match. We have a few days to prepare for this match.

"Each player, when they get home, can look in the mirror and be proud of themselves. We'll analyse the game calmly and see what we can do." 

Flick was, however, upset over several refereeing decisions after Tuesday's game.

Polish referee Szymon Marciniak awarded Inter a penalty after a VAR review for a challenge by Pau Cubarsi on Lautaro Martinez that he initially did not deem to be an infringement, as Hakan Calhanoglou netted the Nerazzurri's second from the spot.

Marciniak also later reversed a spot-kick he had awarded for Barcelona, with the VAR saying Henrikh Mkhitaryan's foul on Yamal occured just outside the box.

In addition, Barca's players and bench complained about what they thought was handball inside the box by Inter defender Acerbi and a foul by full-back Denzel Dumfries on Gerard Martin in the build-up to the equaliser, which took the game to extra time.

"I don't want to talk too much about the referee, but every decision that was 50-50 went (Inter's) way," Flick told a press conference.

"It makes me sad. My team did an excellent job. I don't like talking about the referee. I've told him what I think, but I'm not going to say here what I've said."