The offer represents a premium of 79.1% to the stock's Thursday closing price of $18.43, which gave the Old Trafford club a market capitalization of about $3 billion.
Ratcliffe, also the chair of petrochemicals firm Ineos, would pay more than $1.5 billion for a 25% stake in United if his bid for the soccer club is accepted, Reuters reported in October.
The Glazer family, which made its fortune in real estate, retail and healthcare and owns the NFL's Tampa Bay Buccaneers, bought the team for 790 million pounds in 2005.
The six descendants of American businessman Malcolm Glazer, who died in 2014, together control 96% of Manchester United's voting stock.
The deal was yet to be finalised and remained the subject of ongoing negotiations, Sky News reported on Friday.
Jim Ratcliffe, Phil Noble, Glazer, Ratcliffe, Malcolm Glazer, Richard Arnold, Patrick Stewart, Eva Mathews, Arun Koyyur
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