Sir Philip Green's Arcadia retail group is facing a crucial week, with creditors set to vote on his proposed restructuring plans on Wednesday.
If landlords and the Pensions Regulator do not back his proposals to shut stores and cut rents, the High Street giant could go into administration.
Nearly 50 UK shops are due to close and MPs want him to use his own wealth to fund the firm's pension scheme.
Arcadia chains include Topshop, Burton, Wallis, and Dorothy Perkins.
The measures are seen as a final effort by the company, which is losing out to online rivals, to stave off administration or breakup.
Arcadia currently has more than 560 shops across the UK and Ireland, and employs 22,000 staff.
The firm initially announced 23 stores would close as part of the rescue deal, known as a company voluntary arrangement (CVA). Then it emerged that a further 25 stores would shut, under separate insolvency proceedings.
That second round of closures will mainly affect plus size clothing chain Evans, as well as six Miss Selfridge stores.
The latest closures add to the 200 UK stores shut over the past three years.
Under the CVA, the retail giant is also seeking to halve contributions to its pension funds - which have a deficit of £750m - to £25m each year.
But Sir Philip's wife, Lady Tina Green, who is Arcadia's main shareholder, has offered to inject an extra £100m into the schemes over the next three years.
However, the Pensions Regulator - which has the power to block the CVA - has said it has doubts the plans will "adequately protect" the pensions of employees.
And MP Frank Field, chair of the Commons' Work and Pensions Committee, has urged Sir Philip to use his own money to support the pension fund of his troubled group.
The retail tycoon is also seeking rent reductions on nearly 200 shops, and to sweeten the pill he has offered landlords a 20% stake of any proceeds if the group is eventually sold.
But a number are pushing for changes to the proposals.
For the agreement to go ahead, Arcadia must win approval from three quarters of its creditors, which include landlords, creditors and the company's pension trustees.
'Years of underinvestment'
Retail analyst Richard Hyman told the BBC it was "hard to tell" if the CVA would pass.
"There are big questions over whether Green can make Arcadia a viable business after years of underinvestment.
"He's also had run-ins with his landlords and the Pension Regulator in the past. Now he's asking them to believe in him, and it's a big ask."
But Richard Lim, head of Retail Economics, said landlords had little choice but to back the deal.
"Arcadia has a huge presence on the High Street, and in many places landlords will think, 'who is going to fill this space if they aren't here?'"
The retail group also plans to shut all of its 11 Topshop and Topman stores in the US.
Separately, last week Sir Philip was charged in the US with four counts of misdemeanour assault.
The charges come after a fitness instructor in Arizona alleged that he repeatedly touched her inappropriately.
Sir Philip denies the claims.