Messi told the La Liga giants of his intention to depart having grown frustrated following a Champions League humiliation at the hands of Bayern Munich.
But the six-time Ballon d’Or winner insists the 8-2 defeat wasn’t the only reason he wanted to leave.
Instead, the forward spoke of his disagreements with Barca president Josep Maria Bartomeu, hinting that he’s not overly happy to remain with the club.
Messi had been linked with a move to Manchester City as he thought he could leave on a free, though it was determined any club would have to pay €700m for the superstar.
Lionel Messi statement in full
“I told the club, including the president, that I wanted to go. I've been telling him that all year. I believed it was time to step aside.
I believed that the club needed more young players, new players and I thought my time in Barcelona was over. I felt very sorry because I always said that I wanted to finish my career here.
It was a very difficult year, I suffered a lot in training, in games and in the dressing room. Everything became very difficult for me and there came a time when I considered looking for new ambitions.
It did not come because of the Champions League result against Bayern, no – I had been thinking about the decision for a long time.
I told the president and, well, the president always said that at the end of the season I could decide if I wanted to go or if I wanted to stay and in the end he did not keep his word.
Throughout the year I had been telling the president that I wanted to leave, that the time had come to seek new goals and new directions in my career.
He told me all the time: ‘We'll talk, not now, this and that’, but nothing. The president did not give me a clue at what he was really saying.
Sending the burofax was making it official that I wanted to go and that I was free and the optional year – I was not going to use it and I wanted to go.
It was not to make a mess, or to go against the club, but the way to make it official because my decision had been made.
If I don't send the burofax, it's like nothing happens, I have the optional year I had to have continued all year.
What they say is that I did not say it before June 10 – but I repeat, we were in the middle of all the competitions and it was not the moment.
But apart from that, the president always told me 'when the season is over, you decide if you stay or leave', he never set a date, and well, it was simply to make it official that I wouldn't continue, but not to start a fight because I didn't want to fight against the club.
Of course I had a hard time deciding. It does not come from the Bayern result, it comes from many things. I always said I wanted to end here and I always said I wanted to stay here. That I wanted a winning project and to win titles with the club, to continue expanding the legend of Barcelona.
And the truth is that there has been no project or anything for a long time, they juggle and cover holes as things go by. As I said before, I always thought about the welfare of my family and the club.
When I communicated my wish to leave to my wife and children, it was a brutal drama. The whole family began crying, my children did not want to leave Barcelona, nor did they want to change schools.
But I looked further afield and I want to compete at the highest level, win titles, compete in the Champions League. You can win or lose in it, because it is very difficult, but you have to compete.
At least compete for it and let us not fall apart in Rome, Liverpool, Lisbon. All that led me to think about that decision that I wanted to carry out.
I thought and was sure that I was free to leave, the president always said that at the end of the season I could decide if I stayed or not.
Now they cling to the fact that I did not say it before June 10, when it turns out that on June 10 we were competing for La Liga in the middle of this awful coronavirus and this disease altered all the season.
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And this is the reason why I am going to continue in the club. Now I am going to continue in the club because the president told me that the only way to leave was to pay the €700m (£624m/$823m) clause, and that this is impossible.
There was another way and it was to go to trial," he added. “I would never go to court against Barca because it is the club that I love, which gave me everything since I arrived.
It is the club of my life, I have made my life here.
Barca gave me everything and I gave it everything. I know that it never crossed my mind to take Barca to court.
My son, my family, they grew up here and are from here. There was nothing wrong with wanting to leave. I needed it, the club needed it and it was good for everyone.
My wife, with all the pain of her soul, supported and accompanied me.”