The coffee chain employs 100 different nationalities, with 65% of its workforce coming from EU countries outside Britain, the Guardian has reported.
Andrea Wareham told a House of Lords select committee that Pret would struggle to find enough staff if it was unable to employ EU nationals after Brexit.
She added that the group, which operates more than 250 stores nationwide, found it difficult to recruit British workers, many of whom had a negative perception of the hospitality industry.
“[The difficulty], it’s not in selecting, it’s a difficulty in attracting, I would say one in 50 people who apply to our company to work is British,” said Wareham.
“If I had to fill all our vacancies with British-only people I would not be able to fill them because of the lack of applications.”
She added that while staff at Pret can earn ‘really good money’, British teenagers were still turning their backs on hospitality work.
“It takes a long time to change hearts and minds,” said Wareham. “We need to work with education, career services, with parents, to find ways to collaborate.”
The British Hospitality Association (BHA) estimates that 700,000 EU citizens currently work in the UK hospitality industry.
Brexit secretary David Davis said last month that it would take ‘years and years’ for British workers to fill skills shortages in foodservice jobs.
He added that the UK would not ‘shut the door’ on EU workers after Brexit.