Manchester City could step up their interest in Dani Alves after the defender plunged his Barcelona future into doubt the Daily Star reports.

The Brazil international angered the Catalan giants after taking part in a friendly without permission from the clubs medical staff having only recently undergone surgery on a fractured collarbone.

Alves played around 25 minutes in the game, which also featured teammate Lionel Messi, but landed himself in hot water with Barca now planning disciplinary action according to Spanish newspaper Marca.

Despite committing his future to the Spanish club earlier this month the 29-year-old could leave the Nou Camp in the summer with City boss Roberto Mancini reportedly tracking his progress.

Mancini is keen to bolster the right back position this summer and is hoping to exploit the bad feeling between Alves and Barca after they angered the defender earlier this year by refusing dismiss rumours that he wanted to leave.

Meanwhile, City have opened talks over an extension to the contract of Spain midfielder David Silva after it emerged Barca wanted to bring him back to La Liga.

Silva has two-years to run on his current deal at the Etihad Stadium but the Premier League champions want to reward him for his consistent performances since arriving from Valencia in 2010.

A City delegation flew out to Spain at the weekend to meet with the 26-year-old’s representatives after he indicated a willingness to remain at the club.