The UK government has given planning consent to the £20bn Sizewell C nuclear power plant in Suffolk. The decision by the business secretary, Kwasi Kwarteng, which had been repeatedly delayed, was finally announced on Wednesday and went against the advice of the independent Planning Inspectorate. French energy company EDF wants to build the 3.2 GW, two-reactor plant next to its existing site at Sizewell B, which began operating in 1995. However, the proposals have faced fierce opposition from local campaigners, who have argued against the project because of the environmental impact and the cost to energy billpayers. Campaigners now have six weeks to decide whether to appeal against the decision. Planning permission was seen as a key hurdle for the project which remains subject to a further final investment decision, expected next year. It is hoped the plant can generate enough power for six million homes. The approval process for Sizewell C has so far included four rounds of public consultation which began in 2012 and has involved more than 10,000 East Suffolk residents. The Planning Inspectorate rejected the scheme because of concerns over the plant’s impact on protected species and habitats, and the long-term water supply at the site. EDF worked with Chinese state-backed nuclear specialist CGN on the first phase of the project. However, it is understood the UK government is keen to ease CGN out amid concerns over Chinese involvement with sensitive assets. Bankers at Barclays have been hired to secure new financial backing for the project alongside EDF and the UK government. Boris Johnson’s government put £100m of funding behind the project in January to support its development. Carly Vince, the project’s chief planning officer, said: “Sizewell C will be good for the region, creating thousands of opportunities for local people and businesses. It will boost local biodiversity and leave a legacy Suffolk can be proud of.” Julia Pyke, the director of financing for Sizewell C, said: “Energy costs will be lower with nuclear in the mix, so today’s decision is good news for billpayers. The tried and tested funding arrangement we are proposing means that, by paying a small amount during construction, consumers will benefit in the long-term. “Sizewell C will give a big boost to jobs and skills in nuclear supply chain companies across the country. It will strengthen the UK’s energy security and play a key role in our fight against climate change.” Alison Downes, of the Stop Sizewell C campaign, said: “The wrong decision has been made but it’s not the end of our campaign to Stop Sizewell C. Not only will we be looking closely at appealing this decision, we’ll continue to challenge every aspect of Sizewell C, because – whether it is the impact on consumers, the massive costs and delays, the outstanding technical questions or the environmental impacts – it remains a very bad risk.” Beccy Speight, the chief executive of the Royal Society for the Protection of Birds, said: “The construction of the proposed development will be damaging and it has been granted with insufficient consideration for the effects on nature as described by the government’s own experts. This is a ludicrous decision for an interim government to make.” Greenpeace UK’s chief scientist, Dr Doug Parr, called the project a “red herring energy solution” as the UK attempts to move towards a low-carbon energy system. Tom Greatrex, the chief executive of the Nuclear Industry Association, said the decision “significantly strengthens the pipeline of new nuclear capacity in Britain”. Hinkley Point C in Somerset, also backed by EDF, has been beset by delays and cost over-runs. The French government said on Tuesday it was prepared to pay €10bn (£8.5bn) to fully nationalise EDF amid concerns over its finances. Ministers in France want to keep a handle on soaring energy bills. Johnson has set a target of making investment decisions on eight new nuclear projects by the end of the decade.