The Daily Mail is reporting that Arsenal need to sign a new centre-half this summer after Koscielny made it clear that he wants to leave the north London side this summer.
The same article states that Arsenal have been looking at Dias since the start of the summer transfer window but the Gunners could step up their interest in the Portuguese defender.
According to the same story, the Europa League runners-up were initially concerned that a deal could be too expensive for Dias but Arsenal are now prepared to enter into negotiations with Benfica.
The Daily Mail go on to state that Arsenal are hoping the Portuguese club would be willing to accept a lower fee with future add ons as a sweetener in a deal for the Portugal international.
Arsenal have only signed 18-year-old Gabriel Martinelli in a £1.6m deal from Brazilian club Ituano in the summer transfer window so far.
The north London side conceded 53 times in 38 games in the Premier League last term to highlight their issues at the back.
The Gunners have failed to finish in the top four in the last three seasons.
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