Hundreds of protesters gathered on Sunday to oppose the building of a £20bn nuclear power station.
Carrying banners that read "chaos coast coming soon", "EDF-off" and "we don't want to be beside the C", the crowd marched from Leiston to Sizewell beach in Suffolk.
The demonstration against the construction of the proposed Sizewell C plant took place just days after ministers deferred a final decision on whether to give the project the green light until July.
Earlier this week, the Department for Business, Energy and Industrial Strategy set a new deadline of July 8 as it seeks more information on issues such as water supply.
Negotiations between the Government and French project developer EDF started last year.
Campaigners say the delay is a recognition of the project's problems, including water supply, transport, coastal erosion and biodiversity.
Alison Downes of Stop Sizewell C said: "A decision to go ahead with Sizewell C would be a wrong decision.
"EDF has clearly not taken this community with them, and the government has totally betrayed the faith of local people in due process by repeated commitments to Sizewell C when it doesn't have planning consent, let alone a final investment decision."
Adrian Ramsay, co-leader of the Green Party, added: "Building a nuclear power station with the kind of subsidy the government is talking about will lock in raised electricity prices for years to come.
"Renewably generated electricity is now far, far cheaper and will deliver far more sustainable jobs for Suffolk people and its independent businesses than this expensive white elephant."
The large-scale Suffolk station is part of a fleet of new nuclear power plants at the heart of the Government's energy strategy, in which Prime Minister Boris Johnson last month set out aims to step up nuclear, wind, solar and hydrogen production.
In January, the Government announced £100 million of funding to support Sizewell C's continued development, with the move aimed to attract further financing from private investors.
If built, Sizewell C would power the equivalent of about six million homes, and would support up to 10,000 jobs in Suffolk and across the UK.
Its construction is expected to cost around £20 billion and it would be a near-identical replica of Hinkley Point C, the plant currently under construction in Somerset.
A spokesperson for Sizewell C said: “Sizewell C will deliver 1,500 apprenticeships and 7,900 jobs at peak construction with at least a third of the workforce coming from the local area.
“This is a once in a lifetime opportunity for Suffolk worth billions of pounds to the regional economy and we are committed to ensure Sizewell C brings a positive legacy for local people for generations to come, improving the life chances of some of those furthest from the job market and a boost in local skills, training and education and contracts for the business community."
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