Campaigners have won permission for another hearing to challenge the green light to build the Sizewell C nuclear power station.

The hearing was allowed on the issue of a permanent water supply, and because of the public interest in the development.

Court of Appeal judge Lord Justice Coulson decided that the arguments of campaign group Together Against Sizewell C (TASC) on the need for a desalination plant should be looked at again.

The group can now appeal against Mr Justice Holgate’s decision in the High Court to refuse a judicial review.

The review concerned the former Business Secretary Kwasi Kwarteng’s decision to give development consent to the power station on the Suffolk coast.

The judge said that the appeal had “a real prospect of success” because of TASC’s arguments about the need for a water supply, and because Mr Kwarteng gave permission against the advice of the planning Examining Authority.

TASC had argued that a desalination plant would be needed to guarantee the water supply of 2.2million litres per day for the power station, but the environmental impact of such a plant was not included in the planning application.

The project, led by EDF and backed by the government, aims to produce 3.2 gigawatts of electricity, enough to power about six million homes.

They said the issue of a water supply should not have been treated as a separate issue to the power plant application.

Chair of TASC, Jenny Kirtley, said: "TASC are delighted by the Appeal Court's decision and welcome the acknowledgement that our appeal, challenging the Secretary of State’s approval of Sizewell C, has a ‘real prospect of success’.”

Paul Collins, chair of Stop Sizewell C, added: "Despite this legal challenge it is clear that ministers have now ploughed over a billion pounds of taxpayers' cash into this risky damaging project.

“This flow of funding into Sizewell C should cease until our appeal against the lawfulness of the Secretary of State's decision is resolved."

A spokesperson for Sizewell C said: “These claims have been dismissed twice in the High Court and we will support the Government in defending its decision to award the DCO for this critical piece of national infrastructure.

"The project continues to make great progress as demonstrated by today's launch of the equity raise.”