Confectionery brand Mars has announced it is launching vegan versions of its Galaxy chocolate bars in the UK.

Mars is the first major mainstream confectionery brand to offer a plant-based alternative to milk chocolate.

The new bars, made from hazelnut paste and certified by the Vegan Society, will be available in three flavours: smooth orange, caramel and sea salt, and caramelised hazelnut.

They will go on sale at Tesco stores from Monday and online via Ocado and Amazon soon after, costing £3 for a 100g bar, double the price of the regular Galaxy.

While all dark chocolate is naturally vegan if it has not had milk or cream added to it, milk chocolate is more challenging to adapt because of its dairy content.

Kerry Cavanaugh, marketing director at Galaxy manufacturer Mars Wrigley UK, said the company was “so excited” to introduce the vegan range using a recipe that “doesn’t compromise on the brand’s signature smooth and creamy characteristics”.

“Wherever you look you can’t avoid the vegan buzz in the UK and with the launch of Galaxy Vegan we’re thrilled to be offering vegans, flexitarians and lovers of sweet treats even more ways to choose pleasure with a brand they love.”

Abigail Stevens, trademark marketing manager at the Vegan Society, said: “We are delighted that Galaxy, such a well-known brand, is entering the vegan market and offering more choice – and even more excited that there are three delicious flavours to choose from.”

The announcement was met with excited reaction on social media, although some questioned the price of the new bars.

Another spokeswoman for the Vegan Society, Dominika Piasecka, said: “Vegans are still a minority in the UK which can lead companies to sell products targeted at us at a higher price.

“However, it’s worrying that the production of dairy milk costs so little that companies are able to sell dairy products so cheaply, and we hope the price of the vegan Galaxy bar will lead consumers to question why.”

The bars are also Mars’s first UK confectionery products to be wrapped in compostable film packaging, made from wood fibre and designed to break down in home composting in a few months.

A number of smaller brands market vegan milk chocolate, including Vego, Loving Earth and Moo Free, while Hotel Chocolat has recently expanded its vegan line.