British billionaire Sir Jim Ratcliffe's firm Ineos has officially entered the race to buy Manchester United.
United's owners the Glazer family said in November that they were considering selling the club as they "explore strategic alternatives".
Ineos said the company had "formally put ourselves into the process".
Ratcliffe made an unsuccessful late £4.25bn offer to buy Chelsea last year after owner Roman Abramovich put the London club up for sale.
He said he would have tried to buy the Old Trafford side following the failure to acquire Chelsea but, after meeting with brothers Joel and Avram Glazer, stated that they did not want to sell.
However, since then the Glazers have changed their stance and he has now joined the bidding process.
Ineos group owns Nice in France and Swiss club Lausanne.
United have been owned by the Glazer family since 2005.