The 22-year-old Spain international joined City from Valencia for £20m in August 2020.
Torres scored 16 goals in 43 games for the English champions, winning the English Premier League and League Cup, and reaching the Champions League final earlier this year in his only full season in Manchester.
However, his second season with the Citizens suffered a setback after suffering a broken foot that kept him out of action since October.
Barcelona is looking to strengthen its offensive line after the historic Argentine striker Sergio Aguero was forced to retire due to a heart problem, a few months after joining the Catalan giant.
After being eliminated from the group stage of the Champions League for the first time in 20 years, the Blaugrana face a big test to qualify for the continental competition next season, where they currently occupy seventh place in the Spanish League.
The problem remains that the club was able to register Torres in light of the financial restrictions imposed by the League, which forced him to abandon his legendary Argentine star, Lionel Messi, in favor of French Paris Saint-Germain due to debts.
It is noteworthy that the Catalan club recorded a financial loss of 481 million euros last season, with a total debt of 1.35 billion euros.
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