Sky Sports News broadcast the footage, which it says is courtesy of Splash News, on Friday morning in the UK. The Daily Mail's website also carried the footage.

The clip appears to show new signing Nelson Semedo challenging Neymar during a training session before the Brazil forward reacts angrily and is held back by Sergio Busquets.

Neymar then walks away from the training session, which took place in Miami. Barcelona play Real Madrid in an International Champions Cup match at the Hard Rock Stadium on Saturday.

The incident comes at a time when Neymar, 25, is considering a move to Paris Saint-Germain. A source told ESPN FC last weekend that Neymar and his father have agreed a contract with PSG and it is up to the club to find a way to complete the move without falling foul of financial fair play rules.

UEFA's FFP head has since told L'Equipe he believes PSG will have "done their sums well."

Meanwhile, Paris Saint-Germain right-back Dani Alves has hit out at suggestions that he is trying to sway Neymar's decision over his future.