The news comes as a blow for the Frenchman, who opened the scoring for Barca and has impressed in recent weeks, netting six times in his last 10 outings.
The injury means he is likely to miss both legs of their Copa del Rey quarter-final with Sevilla, and Sunday’s Catalan derby at Girona.
It is also possible that he could be sidelined for the visit of Valencia at the beginning of February, although he should be fit for Barca’s Champions League last-16 meeting with Olympique Lyonnais in February.