The Government is “worryingly complacent” over how it will enforce environmental regulations after the UK leaves the European Union, according to a new House of Lords report.

Peers said European institutions – such as the Commission and the Court of Justice – have played a key role in ensuring member states upheld EU environmental regulations, with threat of heavy fines having a significant “deterrent effect”.

Campaign groups like ClientEarth have also been able to take the Government to court in the UK to force it to come up with an effective plan to cut air pollution to levels considered to be safe.

Under the Government’s plans for Brexit, much of EU law will be transferred onto the British statute book in an attempt to provide some continuity.

But, while the rules will be broadly the same, members of the Lord’s EU Energy and Environment Sub-Committee said an “effective and independent” system of enforcement would be required to “fill the vacuum” left by the European Commission.

This new procedure would need to be powerful enough to ensure the Government and public bodies stayed true to their environmental obligations, they stressed.

But it was clear that the committee did not have confidence that the Government was planning to have such a system in the UK post-Brexit.

“The Government’s assurances that future Governments will, in effect, be able to regulate themselves, along with ministers’ apparent confusion between political accountability to Parliament and judicial oversight, are worryingly complacent,” they said in the report.

“We note the concerns of witnesses [giving evidence to the committee’s hearings] that existing domestic judicial review procedures may be inadequate and costly.

“It will be important for any effective domestic enforcement mechanism to have both regular oversight of the Government’s progress towards its environmental objectives, and the ability, through the courts, to sanction non-compliance as necessary.”

Lord Teverson, who chairs the sub-committee, said the country post-Brexit would need to cooperate particularly closely with the European Union on environmental issues because of their very nature.

“We’re leaving the EU, but not Europe: whether it’s a question of migratory birds, managing our oceans, or air pollution, the environment transcends political boundaries, and the UK’s environment and Europe’s will remain inextricably linked,” he said.

“We heard evidence that 80 per cent of the public support at least the same level, if not higher levels of environmental protection post-Brexit.

“We need to continue to work together and protect our shared environment for future generations.”

How Brexit affected Britain's favourite foods from Weetabix to Marmite Show all 8 1 /8 How Brexit affected Britain's favourite foods from Weetabix to Marmite How Brexit affected Britain's favourite foods from Weetabix to Marmite Weetabix Chief executive of Weetabix Giles Turrell has warned that the price of one of the nation’s favourite breakfast are likely to go up this year by low-single digits in percentage terms. Reuters How Brexit affected Britain's favourite foods from Weetabix to Marmite Nescafé The cost of a 100g jar of Nescafé Original at Sainsbury’s has gone up 40p from £2.75 to £3.15 – a 14 per cent rise—since the Brexit vote. PA How Brexit affected Britain's favourite foods from Weetabix to Marmite Freddo When contacted by The Independent this month, a Mondelez spokesperson declined to discuss specific brands but confirmed that there would be "selective" price increases across its range despite the American multi-national confectionery giant reporting profits of $548m (£450m) in its last three-month financial period. Mondelez, which bought Cadbury in 2010, said rising commodity costs combined with the slump in the value of the pound had made its products more expensive to make. Cadbury How Brexit affected Britain's favourite foods from Weetabix to Marmite Mr Kipling cakes Premier Foods, the maker of Mr Kipling and Bisto gravy, said that it was considering price rises on a case-by-case basis Reuters How Brexit affected Britain's favourite foods from Weetabix to Marmite Walkers Crisps Walkers, owned by US giant PepsiCo, said "the weakened value of the pound" is affecting the import cost of some of its materials. A Walkers spokesman told the Press Association that a 32g standard bag was set to increase from 50p to 55p, and the larger grab bag from 75p to 80p. Getty How Brexit affected Britain's favourite foods from Weetabix to Marmite Marmite Tesco removed Marmite and other Unilever household brand from its website last October, after the manufacturer tried to raise its prices by about 10 per cent owing to sterling’s slump. Tesco and Unilever resolved their argument, but the price of Marmite has increased in UK supermarkets with the grocer reporting a 250g jar of Marmite will now cost Morrisons’ customers £2.64 - an increase of 12.5 per cent. Rex How Brexit affected Britain's favourite foods from Weetabix to Marmite Toblerone Toblerone came under fire in November after it increased the space between the distinctive triangles of its bars. Mondelez International, the company which makes the product, said the change was made due to price rises in recent months. Pixabay How Brexit affected Britain's favourite foods from Weetabix to Marmite Maltesers Maltesers, billed as the “lighter way to enjoy chocolate”, have also shrunk in size. Mars, which owns the brand, has reduced its pouch weight by 15 per cent. Mars said rising costs mean it had to make the unenviable decision between increasing its prices or reducing the weight of its Malteser packs. iStockphoto

Translating EU laws into British legislation would be an “immensely complicated task”, he added.

“The ‘Great Repeal Bill’ is a welcome first step, and we also welcome the Government’s ongoing review of EU legislation, but with many hundreds of regulations, directives, and court judgments, we are not convinced that the Government has yet found a way to deliver the continuity of environmental protection that we all want to achieve,” Lord Teverson said.

“The European Commission and the Court of Justice have played absolutely vital roles in monitoring and enforcing environmental law in the UK.

“The bottom line is that if the UK fails to honour EU environmental law, it will end up in court. That’s going to change after Brexit, but the vast majority of our witnesses were emphatic that an effective and independent domestic enforcement mechanism will still be needed.”

Which celebrities support Brexit and which support Remain? Show all 30 1 /30 Which celebrities support Brexit and which support Remain? Which celebrities support Brexit and which support Remain? David Beckham (REMAIN) The former captain for the England international football team announced on Instagram that he was “voting to Remain”. He said: “We live in a vibrant and connected world where together as a people we are strong. For our children and their children we should be facing the problems of the world together and not alone.” Getty Which celebrities support Brexit and which support Remain? Victoria Beckham (REMAIN) 'I believe in my country, I believe in a future for my children where we are stronger together and I support the remain campaign.' Getty Which celebrities support Brexit and which support Remain? Daniel Craig (REMAIN) Actor He was pictured wearing a white T-shirt with the slogan: 'No man is an island. No country by itself. Vote Remain on 23rd June.' 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Roger Daltrey (LEAVE) Former frontman of iconic rock band The Who.” I am not anti European, but I an anti the present way we are being governed in Europe,” he wrote in The Mirror. “The whole system has been corrupted by political ego and massive government overreach. The Euro being a perfect example… I do not want to be dragged into the kind of Federal State that this present EU is pushing for - with the UK's voice getting smaller and smaller. AFP/Getty Images Which celebrities support Brexit and which support Remain? JK Rowling (REMAIN) The author of the Harry Potter books has expressed concern that "racists and bigots" are directing parts of the Leave campaign. She added: “How can a retreat into selfish and insecure individualism be the right response when Europe faces genuine threats, when the bonds that tie us are so powerful, when we have come so far together? 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He said: "By working together in Europe we make our economy stronger and we give ourselves more influence in the world and we provide future opportunities for young people." Numerous scientists have also voiced their support for Remain, claiming an out vote would badly damage the field. Getty Images for Breakthrough Pr Which celebrities support Brexit and which support Remain? Sol Campbell (LEAVE) – The former England international football star said he is backing Brexit so that young British sporting talent would be nurtured and given greater opportunities at British clubs. He said: "I'm looking at the sporting side - how youngsters aren't getting the opportunities at some of the big clubs and some of the big clubs are bringing in youngsters from 14, 15, 16 and becoming homegrown, which is pushing some of our youngsters out." Getty Images Which celebrities support Brexit and which support Remain? 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Andrea Leadsom, the Environment Secretary, has repeatedly said it is the Government’s ambition for this generation to be the first to leave the environment in a better state than they found it.

However, despite this vague but ambitious pledge, other Conservative politicians have suggested Brexit is an opportunity to cut environmental protections.

And some campaigners have expressed fears of a “bonfire of regulations”.

In a statement, the Department for Environment, Food and Rural Affairs repeated the official mantra.

“Our ambition is to be the first generation to leave the environment in a better state than we found it,” it said.

“We are committed to building on our long history of wildlife and environmental protection and securing the best deal for Britain as we leave the EU.

“We are clear that we are ready to deliver all of this Government’s priorities and will continue to build the right skills, experience, and leadership to deal with the challenges, and take advantage of the opportunities, that lie ahead.”

Animals in decline Show all 8 1 /8 Animals in decline Animals in decline Harbour seal (Phoca vitulina) Where: Orkney Islands. What: Between 2001-2006, numbers in Orkney declined by 40 per cent. Why: epidemics of the phocine distemper virus are thought to have caused major declines, but the killing of seals in the Moray Firth to protect salmon farms may have an impact. Alamy Animals in decline African lion (Panthera leo) Where: Ghana. What: In Ghana’s Mole National Park, lion numbers have declined by more than 90 per cent in 40 years. Why: local conflicts are thought to have contributed to the slaughter of lions and are a worrying example of the status of the animal in Western and Central Africa. Animals in decline Leatherback turtle (Dermochelys coriacea) Where: Indonesia, Malaysia, Mexico, Costa Rica. What: Numbers are down in both the Atlantic and Pacific. It declined by 95 per cent between 1989-2002 in Costa Rica. Why: mainly due to them being caught as bycatch, but they’ve also been affected by local developments. Alamy Animals in decline Wandering albatross (Diomedea exulans) Where: South Atlantic. What: A rapid decline. One population, from Bird Island, South Georgia, declined by 50 per cent between 1972-2010, according to the British Antarctic Survey. Why: being caught in various commercial longline fisheries. Alamy Animals in decline Saiga Antelope (Saiga tatarica) Where: Kazakhstan, Mongolia, Russia, Turkmenistan, Uzbekistan. What: fall in populations has been dramatic. In the early 1990s numbers were over a million, but are now estimated to be around 50,000. Why: the break up of the former USSR led to uncontrolled hunting. Increased rural poverty means the species is hunted for its meat Animals in decline Swordfish (Xiphias gladius) Where: found worldwide in tropical, subtropical and temperate seas. Why: at risk from overfishing and as a target in recreational fishing. A significant number of swordfish are also caught by illegal driftnet fisheries in the Mediterranean Animals in decline Argali Sheep (Ovis mammon) Where: Central and Southern Asian mountains,usually at 3,000-5,000 metres altitude. Why: domesticated herds of sheep competing for grazing grounds. Over-hunting and poaching. Animals in decline Humphead Wrasse (Cheilinus undulatus) Where: the Indo-Pacific, from the Red Sea to South Africa and to the Tuamoto Islands (Polynesia), north to the Ryukyu Islands (south-west Japan), and south to New Caledonia. Why: Illegal, Unregulated and Unreported (IUU) fishing and trading of the species

It did not address the sub-committee’s concern that it was complacent about the enforcement of environmental protections after Brexit.

ClientEarth has twice gone to court to force the Government to come up with a better plan to reduce air pollution – blamed for the premature deaths of some 40,000 people a year in the UK – in order to comply with EU air quality legislation that is expected to be transferred into British law after Brexit.

It is also threatening to sue the Government for allegedly breaching the UK Climate Change Act by repeatedly delaying publication of its Emissions Reduction Plan, which is the main method by which Britain will live up to its international commitments to reduce global warming.

Catherine Weller, a senior ClientEarth lawyer, said: “The House of Lords today confirmed the immense risk to the UK environment posed by Brexit, saying that maintaining existing standards through the ‘Great Repeal Bill’ will be a hugely complex task.

"As a first step, the Government must enshrine current environmental protections in law – we’ll be watching the detail to ensure that they do, and that they don’t sneak in a way to undo these protections overnight.

“The Lords rightly highlighted the danger of a lack of oversight and enforcement once the UK leaves the EU. We agree that a strong, independent domestic mechanism is crucial to make sure effective environmental laws are made and followed.