The Spanish club released a statement on Tuesday in which they confirmed their intention of bringing legal action against Neymar in the wake of his £198m transfer to Paris Saint-Germain earlier this summer.
Barcelona said they were seeking £7.8m in damages and an additional 10 per cent in arrears linked to a bonus for the renewal of his contract, which he signed at the club last October and which tied him down to the La Liga outfit until 2021.
It comes after Neymar, who has scored three goals in two games for PSG, criticised the Barcelona board when he said: "I don't have anything to say to the Barcelona board.
"Well, actually I have something to say: That I am disappointed with them.
"I spent four years there and was very happy. I began happy, spent four years happy and left happy. But not with them.
"For me, they shouldn't be in charge of Barca. Barca deserve much better, and everyone knows this."
