Disappointment was voiced last night over renewed uncertainty for Suffolk residents waiting for a decision on Sizewell's new nuclear reactors.

Union leaders said a setback to the Hinkley Point power station in Somerset was 'bad news' for the country – creating the 'very real prospect' of power cuts in the years ahead with not enough electricity for the UK's growing demands.

EDF Energy said Hinkley Point C would not start generating electricity in 2023 as planned. The timeline of Hinkley Point and Sizewell C has always been linked – though officials insisted the delays would have no impact on the Suffolk project.

Geoff Holdcroft, Suffolk Coastal District Council's deputy leader and chairman of its Sizewell C task group, said: 'The news about Hinkley Point C is disappointing as it will prolong the uncertainty about Sizewell C for local people.'

The Unite union's Kevin Coyne said: 'This delay is very bad news for the UK as energy capacity is very stretched at present, as we have lost energy resources in recent years as old coal-fired stations are phased out,' adding that there was a real prospect of power cuts if the decision was not made soon.