By London correspondent Tony Hughes

Arsenal are set to be frustrated in their pursuit of Valencia defender Shkodran Mustafi, according to a reliable journalist.

Sky Sports’ Spanish expert Balague claimed on Monday afternoon that the Gunners are likely to miss out on the centre-back just 24 hours after Arsene Wenger said he was hopeful a deal for the player “will be done” before the transfer deadline.

This comes after widespread reports earlier this month that Mustafi had agreed personal terms with Arsenal following a defensive injury crisis at the London club.

However, Mustafi’s buy-out clause now seems likely to prove a major stumbling block in the possibility of him becoming a late August signing.

“The coaching staff at Valencia think Mustafi will not go, and this is the same message being made by Valencia,” said Balague, as quoted by the Sky Sports website.

“They insist the only way Mustafi will be allowed to leave is if Arsenal trigger his €50m (£43.1m) buy-out clause, which I think everybody will agree is too much money for him.

“Valencia’s position is such because they don’t think they can find someone to replace him, given the proximity of transfer deadline day. It’s a similar stance to the one they have with Barcelona target Paco Alcacer, or at least that’s the message they are giving out.

“So, as things stand, neither Mustafi nor Alcacer will be leaving Valencia. I heard Arsene Wenger confirm publicly that Arsenal were in negotiations for Mustafi. That’s very rare for him to do so. Perhaps he is trying to apply some pressure on Valencia to sell.

“Valencia have had difficulties with Financial Fair Play, but that has improved recently. They still need to sell one or two players, but they would rather part with the likes of Aderlan Santos or Lucas Orban, sales which they believe would bring the club in line with the regulations.

“So they are not as desperate as some are making them out to be.”

Wenger was once again forced into a staunch defence of his transfer policy on Saturday after calls from supporters to spend money following Arsenal’s 0-0 draw at Leicester.

The Gunners manager told French TV station SFR Sport:Mustafi? We hope it will be done  He is one of a number of players we are looking at. Negotiations are ongoing.”

Arsenal have had issues at centre-back since a long-term injury to Per Mertersacker ruled him out until the New Year and Gabriel Paulista is also sidelined for six weeks.

In other Arsenal transfer news, these two former players are set for an unlikely reunion in Turkey.