Dembele is expected to leave for free at the end of the season after he decided against renewing his contract in January.
But the Frenchman has been revitalised by Xavi Hernandez and his agent reportedly met with Barca's sporting director Mateu Alemany this week, raising hopes again that an agreement might be reached.
"I would kidnap him to make him stay," said Torres in a press conference ahead of the first leg of Barcelona’s Europa League quarter-final against Eintracht Frankfurt on Thursday.
"He is a difference-maker. He is one of the best players in the world and this is a great club to be at. The decision is his and I wish him the best."
Barcelona told Dembele in January he either had to extend his contract or leave but Xavi has decided to make use of the 24-year-old in the team's pursuit of La Liga's top four.
Dembele's excellent form has been integral to Barca's surge up the table. The team sit second, with Champions League qualification all-but secured.
"I hope he stays," said Xavi. "We don't have the best financial situation in history and we have to adjust to that but I hope he can stay. For me he's fundamental."
Xavi also confirmed Ronald Araujo is set to sign a new contract with the club.
The 23-year-old defender has played 38 games for Barcelona this season and is considered one of the club's most promising young players.
"For us, it is a guarantee," Xavi said. "Barca has a central defender for ten years or more. There are few players of his level in the world."
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