Sir Jim Ratcliffe has completed his purchase of a 25 per cent stake in Manchester United and will be given footballing control of the club.

The Ineos billionaire, a lifelong United fan, has paid £1.3bn for Class A and B shares from the Glazer family, who retain the biggest part of the club, and will provide an extra $300m (£236) for investment in Old Trafford. Two-thirds of that will be available immediately, with the rest to follow by the end of 2024.

The petrochemicals magnate Ratcliffe vowed to try to unlock United’s potential and take them back to the top of English and European football. Erik ten Hag’s struggling team are currently eighth in the Premier League and were knocked out of the Champions League after finishing bottom of their group.

The sale of the stake to Ratcliffe ends a 13-month takeover process in which United also explored a sale, with the Qatari banker Sheikh Jassim making five bids, and Ineos first looking for a full buyout and then amending their offer to minority investment.

The deal values United at more than £5bn with shares priced at $33, far higher than their value on the stock market while Ineos’s footballing control is expected to bring roles for Ratcliffe’s allies. The cycling supremo Sir Dave Brailsford and the former Juventus CEO Jean-Claude Blanc are set to take Ratcliffe’s seats on the club board with those on the PLC board going to Rob Nevin, the chair of Ineos Sport, and John Reece, a shareholder in Ineos. The new regime is also expected to appoint a new chief executive, with Richard Arnold standing down.

Ratcliffe said: “As a local boy and a lifelong supporter of the club, I am very pleased that we have been able to agree a deal with the Manchester United board that delegates us management responsibility of the football operations of the club. Whilst the commercial success of the club has ensured there have always been available funds to win trophies at the highest level, this potential has not been fully unlocked in recent times. We will bring the global knowledge, expertise and talent from the wider Ineos Sport group to help drive further improvement at the club, while also providing funds intended to enable future investment into Old Trafford.

“We are here for the long term and recognise that a lot of challenges and hard work lie ahead, which we will approach with rigour, professionalism and passion. We are committed to working with everyone at the club – the board, staff, players and fans – to help drive the club forward.

“Our shared ambition is clear: we all want to see Manchester United back where we belong, at the very top of English, European and world football.”

The Glazers acquired United for around £800m in 2005 in a leveraged buyout. Executive co-chairs Avram Glazer and Joel Glazer said: “We are delighted to have agreed this deal with Sir Jim Ratcliffe and Ineos. As part of the strategic review we announced in November 2022, we committed to look at a variety of alternatives to help enhance Manchester United, with a focus on delivering success for our men’s, women’s and academy teams.

“Sir Jim and Ineos bring a wealth of commercial experience as well as significant financial commitment into the club. And, through Ineos Sport, Manchester United will have access to seasoned high-performance professionals, experienced in creating and leading elite teams from both inside and outside the game. Manchester United has talented people right across the club and our desire is to always improve at every level to help bring our great fans more success in the future.”

Ineos’s sporting portfolio includes Nice football club and investments in cycling, Formula One, sailing and rugby.

The deal will have to be approved by the Premier League, which is expected to take up to eight weeks.

United fans may also be unlikely to see immediate signings in the January transfer window. The club is expecting a quiet month because it is worried that bringing in big-money buys could mean breaching Financial Fair Play regulations.