Todd Boehly promised to build on Chelsea’s “remarkable history of success” after the American’s consortium completed its £4.25bn takeover of the club on Monday.

A new era at Stamford Bridge is under way after Roman Abramovich agreed to the UK government’s terms for the sale. Chelsea described the deal as unprecedented in its speed, saying such a transaction would normally take nine months, and revealed they received more than 250 inquiries after Abramovich put the club up for sale in March.

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The process was eventually won by a consortium led by Boehly, the part-owner of the LA Dodgers, and the US investment firm Clearlake Capital. The group includes the Swiss billionaire Hansjörg Wyss, the British property developer Jonathan Goldstein and Mark Walter, Boehly’s fellow Dodgers owner. It is expected that Marina Granovskaia, who runs Chelsea’s transfer business, and Bruce Buck, the chairman, will remain.

“We are honoured to become the new custodians of Chelsea Football Club,” Boehly said. “We’re all in – 100% – every minute of every match. Our vision as owners is clear: we want to make the fans proud. Along with our commitment to developing the youth squad and acquiring the best talent, our plan of action is to invest in the club for the long term and build on Chelsea’s remarkable history of success. I personally want to thank ministers and officials in the British government, and the Premier League, for all their work in making this happen.”

The deal was signed off a day before Chelsea’s operating licence was due to expire. Nigel Huddleston, the sports minister, confirmed that the club would no longer be affected by the sanctions imposed on Abramovich after Russia’s invasion of Ukraine.

The Russian oligarch has agreed to the government’s demand for the initial £2.5bn from the sale to be placed into an escrow account, where it will be held until it is clear the funds will go to a charity for victims of the war in Ukraine. The 55-year-old also agreed not to call in his £1.6bn loan to Chelsea.

Behdad Eghbali and José E. Feliciano, Clearlake co-founders and managing partners, said: “We are excited to commit the resources to continue Chelsea’s leading role in English and global football, and as an engine for football talent development. We also want to thank the authorities for all their work throughout the process.

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“As pioneers in sports and media investing, we are thrilled to partner with Todd and the rest of the consortium to meaningfully grow the Club as a global platform. Together, we will expand the Club’s investment across infrastructure, technology, and sports science to support the incredible Chelsea football and commercial teams – all with the goal of leveraging this growth to fuel even more on-pitch success.”

Chelsea, who were previously unable to make signings, sell players and hand out new deals, can now enter the transfer market. Their owners are set to give Thomas Tuchel significant funds to strengthen his squad.