Pret A Manger is giving away free vegan croissants on Friday afternoon to "reward customers completing Veganuary".

You just need to head to participating Pret and Veggie Pret shops across the country between 3pm and 4pm, quoting the secret password which will be shared on Pret’s social media channels.

Pret say the vegan Very Berry Croissant has been a huge hit with customers since launching in early January, with it selling more than double the amount per day of the non-vegan jam croissant it replaced.

It uses margarine and sunflower oil to re-create the buttery, light texture of a traditional croissant. The pastry is then filled with a sweet berry compote and finished with a sprinkling of sugar.

Vegans and non-vegans alike have already shared their love for the product on social, with one Instagram user proclaiming, "OMG I tried this the other day and it was amazing, didn’t even realise it was vegan!" and another stating, "I’ve been missing pastry that’s lovely and tasty."

The password will be revealed on Pret’s social media accounts over the next couple of days @Pret on Twitter; Pret A Manger on Facebook and @Pret on Instagram).