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 mentioned it might depart the setting in a greater state for future generations.
However the letter expresses concern that Brexit might pressure ministers to backtrack on this promise.
Quantity 10 mentioned it might examine the letter earlier than responding.
Newspaper reports primarily based on leaked documents have instructed that commerce and development 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 studies suggesting that the UK’s commitments to tackling local weather change and ending the unlawful wildlife commerce may very well be watered all the way down to safe post-Brexit commerce offers.”
It added: “To be an ideal, world buying and selling nation, the UK should ship on its guarantees for the setting and the local weather and honour our worldwide commitments.
“In doing so we’ll assist construct a greener, higher and extra affluent future for everybody, quite than driving an environmental race to the underside.”
Marketing campaign teams which have signed the letter embody WWF, the Born Free Basis, Cafod, Associates of the Earth, Greenpeace and Oxfam.
Plenty of high-profile people are additionally signatories: they embody 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 obtained 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 regulation,” Trevor Hutchings, director of advocacy at WWF-UK, advised BBC Information.
These protections embody a bundle of laws to make sure the EU meets local weather and power targets for 2020. He mentioned the EU establishments additionally supplied a strict system of accountability, in order that fines may very well be invoked if member states didn’t ship on their obligations to the setting.
“We, on the one hand, welcome the federal government’s dedication to nature and to bringing these legal guidelines over by the Nice Repeal Invoice… however in latest weeks quite a lot of issues have occurred that query that dedication,” Mr Hutchings defined.
He mentioned 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 mentioned 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) mentioned officers would take a look at the element of the letter earlier than issuing a response.
However sources mentioned the federal government’s dedication to inexperienced points remained as robust as ever.
However, some observers inside the environmental neighborhood have expressed issues that inexperienced points might grow to be bargaining chips within the effort to safe commerce offers.
“Environmental laws and requirements do make up so-called non-tariff commerce boundaries – as some individuals may understand them,” mentioned Mr Hutchings.
“It most likely does not come as a shock that a few of these non-tariff boundaries might grow to be a central negotiating level for commerce offers with nations which have decrease requirements. That is the worry, although we haven’t any clear proof of that.”
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