Pret A Manger has appointed advisors to lead rent renegotiations with landlords.
Alvarez & Marsal and CWM are to advise the grab-and-go chain, which has more than 500 UK stores, on a "comprehensive transformation plan".
Chief executive Pano Christou said: "Like the rest of the industry, we have been radically adapting our business model to succeed in the face of the changing market conditions. Reduced footfall, combined with high rental costs, have placed substantial pressure on our business.
"We are putting together a clear plan to address these issues and are already making good progress, with more than 300 shops up and running again as of next week. While Pret may look and feel a bit different in the short term, if we take the right steps today, we'll make sure Pret can thrive in the future and serve even more customers with great food and coffee."
Pret A Manger has opened another 204 outlets for takeaway and delivery today, taking the total stores operating to more than 300.