The England midfielder completed his move to the London Stadium on Monday after having been heavily linked with a switch to the Hammers.
Wilshere was left looking for a new club after new Arsenal manager Unai Emery determined him to be surplus to requirements at The Emirates and told him to look for a new team.
The midfielder had been a regular fixture in the Arsenal team towards the end of last season but Wilshere is now getting used to his new surroundings with the Hammers.
Now, after completing his move to West Ham United from Arsenal, Wilshere has spoken of his delight at sealing the transfer.
Wilshere wrote on Instagram: “Delighted to have officially signed for West Ham United! After speaking with the manager and those at the club I knew my future was at the London Stadium and I can’t wait to get going now.
“It’s well known that I come from a family of Hammers and it’s a special moment to sign for the club I used to go and watch as a boy.
“The West Ham fans are some of the very best and I am looking forward to giving everything I have to helping the team to bring success to you all.
“I’m excited for the future at this great club. Off to training camp and the hard work starts now. Come on you Irons!”
Arsenal, meanwhile, are still believed to be on the lookout for a number of new signings this summer as they look to assemble a team capable of winning the Premier League title next season.
Emery has been tasked with at least steering the Gunners back into the top four after they finished in sixth place in the table last term and without a trophy.
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