Messi: We cannot let this chance slip
Both Atletico and Real Madrid have stuttered in recent weeks to leave the title race wide open, and Barca will triumph if they win their last two games.
They face Elche this weekend before the final game of the season against Atletico at the Camp Nou and Messi has urged his team-mates to retain their focus.
"Now we are in a better position compared to in previous weeks," said Messi. "You can see that now we have a chance in the league, and it is up to us.
"We are not depending on results going our way.
"We must take advantage of this moment and not allow it to get away from us."
The 26-year-old was also keen to stress that he is very happy at the Catalan giants and has no intention of leaving the club, contrary to reports.