PRET a Manger is to embark on its biggest ever menu shake-up as the sandwich chain rings the changes following its £1.5 billion takeover.

A total of 20 new products are being added to the food firm's offering next week, with many targeted at "flexitarians", vegans and vegetarians.

They will include food that can be eaten "any time of the day" to accommodate snacking, and Pret is also introducing its own gluten-free bread following strong demand from customers.

Pret's head of food development Hannah Dolan described it as the "biggest change in our history".

"Two-thirds of Pret products are now purchased outside of the lunchtime period, and we think these filling snacks and smaller meals will fit really well with our customers' busy schedules," she said.

Last year the group was sold for £1.5 billion to JAB, the investment vehicle of Germany's wealthy Reimann family.

It preceded a difficult period for the firm, which saw Pret introduce full ingredient labelling on every product after a 15-year-old died from an allergic reaction to a baguette bought at Heathrow Airport branch.

The 20 new products include salad pots, vegan and meaty open sandwiches, new desserts, vegan breakfast birchers and a bircher smoothie.

Pret has over 500 stores worldwide and is rapidly expanding globally in countries such as the US, China and France.

JAB is also behind Krispy Kreme donuts, Kenco coffee and Dr Pepper.