Environmental teams have urged the prime minister to keep away from watering down laws on local weather change and wildlife safety after Brexit.
The letter, signed by WWF, Greenpeace and others, says motion is required to halt ongoing environmental decline.
The UK authorities beforehand stated it might go away the atmosphere in a greater state for future generations.
However the letter expresses concern that Brexit may power ministers to backtrack on this promise.
Quantity 10 stated it might examine the letter earlier than responding.
Newspaper reports primarily based on leaked documents have steered that commerce and progress could be prioritised on the expense of efforts to sort out world warming and the unlawful commerce in wildlife.
The letter says: “We’re alarmed by latest media experiences suggesting that the UK’s commitments to tackling local weather change and ending the unlawful wildlife commerce might be watered right down to safe post-Brexit commerce offers.”
It added: “To be an excellent, world buying and selling nation, the UK should ship on its guarantees for the atmosphere and the local weather and honour our worldwide commitments.
“In doing so we are going to assist construct a greener, higher and extra affluent future for everybody, relatively than driving an environmental race to the underside.”
Marketing campaign teams which have signed the letter embrace WWF, the Born Free Basis, Cafod, Pals of the Earth, Greenpeace and Oxfam.
Numerous high-profile people are additionally signatories: they embrace Andy Murray, Anna Friel, Will Younger, Lord Stuart Rose and environmentalist Sir Crispin Tickell.
“A majority of environmental protections derive from the EU – we have most likely received the world’s main environmental framework. In order the UK leaves the EU, the danger is that a few of these protections do not get introduced over into UK legislation,” Trevor Hutchings, director of advocacy at WWF-UK, informed BBC Information.
These protections embrace a bundle of laws to make sure the EU meets local weather and power targets for 2020. He stated the EU establishments additionally offered a strict system of accountability, in order that fines might be invoked if member states didn’t ship on their obligations to the atmosphere.
“We, on the one hand, welcome the federal government’s dedication to nature and to bringing these legal guidelines over via the Nice Repeal Invoice… however in latest weeks a lot of issues have occurred that query that dedication,” Mr Hutchings defined.
He stated this included not solely the leaked memo, but additionally the delayed release of the government’s 25-year plan for nature in England and the Clear Progress Plan on lowering carbon emissions, which Mr Hutchings stated was anticipated earlier than March this yr.
“Issues like entry to environmental data, the ‘precautionary precept’, the ‘polluter pays’ precept are all established in EU treaties. The sense is that these won’t come throughout [into UK law],” he defined.
Spokespeople for Quantity 10 and the Division for Surroundings, Meals and Rural Affairs (Defra) stated officers would take a look at the element of the letter earlier than issuing a response.
However sources stated the federal government’s dedication to inexperienced points remained as robust as ever.
Nonetheless, some observers throughout the environmental group have expressed considerations that inexperienced points may develop into bargaining chips within the effort to safe commerce offers.
“Environmental rules and requirements do make up so-called non-tariff commerce limitations – as some folks may understand them,” stated Mr Hutchings.
“It most likely would not come as a shock that a few of these non-tariff limitations may develop into a central negotiating level for commerce offers with international locations which have decrease requirements. That is the worry, although we have no clear proof of that.”
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