The Restaurant Group (TRG), which operates brands including Wagamama and Frankie & Benny's, is expecting a “large number” of sites to not reopen.
In an email to staff seen by the BBC, TRG said many sites are "no longer viable to trade and will remain closed permanently".
The Restaurant Group declined to comment and could not confirm which sites or how many would remain closed.
TRG filed notice to put Chiquito into administration in March, a move which will permanently close the majority of the 81 Tex-Mex brand's sites.
The Restaurant Group had already announced last year that it would close more than 150 outlets, including Chiquito and Frankie & Benny's sites, as part of a restructure over the next six years, following its acquisition of Wagamama for £559m.
The group raised £57m through a share placing in April aimed to provide the company with "sufficient" liquidity to continue to operate through the coronavirus crisis. However, it issued a "pessimistic scenario for the current financial year" at the time, with the possibility that only 400 of its 600 sites will reopen.
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