Pret a Manger has embarked on a charm offensive to attract more British workers as it faces up to potential staff shortages after Brexit.

“Traditionally at Pret we just had our recruitment centre and everybody just came to us,” said its chief executive, Clive Schlee. “Now we are preparing for the future by reaching out ourselves.”

The company had relied on its own website, which directs applicants to a recruitment centre in London, but has now started using jobcentres and social media adverts to appeal to British candidates.

The high street chain told a parliamentary committee in March that just one in 50 job applicants were British because its upmarket sandwich shops were not seen by Britons as a “desirable place to work”.

With 65% of its workforce drawn from EU countries other than Britain, Pret’s director of human resources, Andrea Wareham, told MPs it would struggle to find enough staff if it was forced to turn its back on EU nationals after the UK leaves the European Union.

Pret’s attempt to appeal to British school leavers got off to a rocky start last month when the company came under fire after the Guardian reported it was offering 500 teenagers a week of work experience, without pay, to give them a taste of working for the private equity-backed firm. The 16- to 18-year-olds were only being offered free food. However, after a backlash on social media the company relented, with Schlee committing to pay all participants Pret’s hourly starting rate.

In recent months a number of UK employers have voiced concerns about their ability to fill jobs in shops, factories and hospitals if EU migrants decide to return home. Schlee told the Financial Times that Pret had not yet seen a decline in the number of EU workers seeking jobs but it was making a concerted effort to tap “more UK-oriented labour pools”.

Schlee said he was encouraged by government plans to head off recruitment woes for the hospitality industry with a new “barista visa” mooted to allow young European citizens to continue coming to the UK to work in coffee shops and pubs.

His comments came as the company reported a record set of full-year results, with global sales rising 15% to more than £776m last year. The chain’s operating profits increased 11% to more than £93m.

Schlee said the pound’s fall since the Brexit vote had been a double-edged sword as it had boosted UK sales by attracting more tourists but had also forced up the cost of many ingredients. He pledged to keep price rises below inflation, despite seeing spikes in the cost of imported ingredients such as salmon, avocados and crayfish.

Pret has won a legion of loyal customers thanks to its ability to spot the latest food trends, such as avocado, quinoa and chakalaka beans. Pret said the most popular new ingredient over the past year had been coconut, with pots of dairy-free coconut porridge now accounting for one in every five sold in the UK. .

The 30-year-old company was founded by the entrepreneur Julian Metcalfe, who went on to create the Itsu restaurant chain and Metcalfe’s Skinny popcorn.

It is now controlled by private equity firm Bridgepoint but there has been speculation that it is gearing up for a stock market flotation within the next 18 months, with further speculation that bosses are eyeing a listing in New York rather than London. The chain has been a big hit in the US, where sales broke the $200m (£155m) mark for the first time in 2016.