Education caterer Edwards & Ward has signed the Sustainable Fish Cities pledge, which will see nearly 40,000 school pupils offered sustainable fish as part of their school meals.
The catering firm has committed to using only sustainable fish across its whole business, which serves more than 7.5 million meals per year.
Edwards & Ward has joined the likes of Brakes, the National Trust, Eurostar, NHS Wales and Google, which have all signed the pledge.
The pledge will help support fisheries and farms that are working sustainably and with lower impact on the marine environment.
Ruth Westcott, co-ordinator of Sustainable Fish Cities, said: "This is a great commitment from Edwards & Ward. We are aiming to see only verifiably sustainable fish on menus in the UK by creating a network of Sustainable Fish Cities.
"There are currently 15 UK towns and cities involved in the campaign, and Edwards and Wards' pledge will be a big boost to London's ambitions."
"We were taking action towards sustainable fish as part of the Food for Life Catering Mark - this pledge will develop that commitment, and mean that we will now raise awareness about overfishing and choosing sustainable fish with our pupils and parents."
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