BBC Sport's John Watson explains the story behind the transfer ban that has been placed on Barcelona.

On Wednesday, Fifa announced that it had banned the Spanish champions from signing any players for the next two transfer windows, meaning the Catalan club cannot buy players until the summer of 2015.

The embargo is significant as the club are planning to replace captain Carles Puyol and sign a new goalkeeper at the end of the season, with the long-serving Victor Valdes leaving the Nou Camp at the end of his contract.