Declan Rice became the most expensive British player in history as Arsenal signed the England midfielder from West Ham for a reported £105 million ($137.5 million).
Rice's fee surpassed the previous record £100 million that Manchester City paid Aston Villa for Jack Grealish in 2021 as Arsenal continues its spending spree in a bid to challenge for the Premier League title next season.
The sum is just below the British record transfer fee Chelsea paid Benfica in January to bring Enzo Fernandez to Stamford Bridge for £106.8 million.
Neither club officially announced the fee, but West Ham said they would receive a record transfer fee between two British clubs for Rice, 24.
Rice said in a farewell letter to West Ham supporters his desire to play at the "very highest level" lay behind his decision to join Arsenal.
His switch to the Emirates Stadium on a five-year contract comes after he lifted West Ham's first major trophy since 1980 in the Europa Conference League final against Fiorentina.
Having moved across London, Rice will now be competing for the Champions League rather than Europe's third-tier trophy.
"In football, amazing opportunities arise. Big clubs, like Arsenal, have come for me and it's really hard to turn down," Rice told Arsenal's website. "You only ever get one career and I really believe in what Mikel (Arteta) is building here and the squad he's building. I'm really looking forward to the future with Arsenal."
Fueled by their agonising failure to hold off champion Manchester City in the Premier League title race last term, the Gunners have already spent around £200 million this summer in a bid to improve on their second-place finish.
Arsenal has not won the title since Arsene Wenger's 'Invincibles' in 2004, but it made huge strides under Arteta last season. It led the Premier League standings for much of the season before collapsing in the final weeks as City's deep squad overhauled them.
Rice is confident the future is bright for a young Arsenal team featuring emerging stars like Bukayo Saka, William Saliba and Gabriel Martinelli.
'Really hungry.' "With Mikel and how he works, the squad, how young everyone is, the energy around the club and also the challenge of getting Arsenal back to where they belong, that means a lot to me," Rice said. "I know the fans really want that. For me as a player, I've come here really hungry to have more success and to spend my best years at this great club.
"I know he (Arteta) is going to get the best out of me. I know I've got more levels to go up in my game and I feel like he's the manager to take me to those next levels."
Jude Bellingham's transfer from Borussia Dortmund to Real Madrid could eventually beat Rice's record as depending on add-on clauses it might reach £115 million.
For now, Rice has a gigantic fee to justify after he joined Germany forward Kai Havertz and Netherlands defender Jurrien Timber as the new recruits in Arteta's squad.
With Granit Xhaka leaving to join Bayer Leverkusen, Rice's arrival will bolster Areta's midfield options.
"Declan is bringing undoubted quality to the club and he is an exceptional talent who has the potential to be very successful here," Arteta said.
Rice, released as a 14-year-old by Chelsea, went on to make 245 appearances for West Ham.
Hammers joint chairman David Sullivan insisted Saturday the club had wanted to keep Rice but were hamstrung by an agreement allowing him to leave after he rejected the offer of a lucrative new deal.
"I would like to make it clear to our supporters that we did not want to sell Declan," said Sullivan. "We wanted to build our team around him and made a series of improved, long-term contract offers to secure his future."
Hammers manager David Moyes added: "Obviously, it is sad when we say goodbye to someone who has been with us for so long but we must now look forward."
© Agence France-Presse