By London correspondent Tony Hughes

Granit Xhaka has completed the first stage of an Arsenal medical after agreeing the terms of a contract worth £31million, Football Insider sources understand.

Xhaka is set to be officially unveiled as a Gunners player  after leaked pictures emerged on Twitter on Saturday morning of him posing in an Arsenal kit.

As reported by Football Insider, the Swiss international flew into London on Friday to complete his transfer from Borussia Mochengladbach.

He has undergone the first part of a medical at the Gunners’ headquarters and has been pictured posing for what appear to be the club’s official photographers ahead of his unveiling as the club’s first signing of the summer.

Xhaka was also photographed with his family outside the main building of the club’s London Colney headquarters and was also pictured in full kit inside the club’s base.

Sources close to the situation have told Football Insider that Xhaka has agreed the terms of a five-year contract worth £120,000-a-week.

His salary is worth £31million over five years while Arsenal will also pay around £34million for the Swiss sensation in a deal that will be worth £65million in transfer fee and wages.

Xhaka, 23, will also become the second-most expensive signing in the club’s history behind Mesut Ozil, who joined from Real Madrid in 2013 for £34million rising to £40million with add-ons.

The Swiss international has made it clear he is likely to leave Borussia this summer and appeared to say goodbye to fans, fellow players and coaches during his final Bundesliga game last weekend.

He also gave a big hint he was on his way by liking an image on Instagram of an Arsenal fan in a Xhaka 34 shirt with the caption: “Welcome my bro”.

The Bundesliga club revealed on their official website on Tuesday afternoon they have received an offer for the central midfielder.

Arsenal are now confident of completing the signing of the Swiss sensation as they target a proven player who can dominate in the middle of the park.

The Gunners signed Mohamed Elneny from Basel in January and are now keen on another former player of the Swiss club.

Basel academy graduate Xhaka moved to Borussia Mochengladbach in 2012 for £6.75million and has developed into one of the Bundesliga’s outstanding midfielders.

In other Arsenal transfer news, the Gunners are expected to field a £25million offer for one of their star names.