The final decision on plans for a £20bn large-scale nuclear plant on the east coast of England has been delayed.
The government said it needed more time to look at new information regarding Sizewell C in Suffolk, and has pushed back the deadline for its final decision to no later than 8 July.
It had been due to make a final call by 25 May.
Campaigners said the delay was "down to dozens of really difficult problems" with the plans.
French developer EDF wants to build the new two-reactor station directly to the north of the existing Sizewell B plant.
Those against the plans argue expanding the use of nuclear is slow, expensive and threatens wildlife.
The government said the new deadline was to ensure there was "sufficient time to fully consider further information provided by the applicant and interested parties in response to the secretary of state's post-examination consultation".
Alison Downes, from campaign group Stop Sizewell C, said it felt problems with the plans included water supply, transport, coastal erosion and biodiversity.
"More importantly, it questions a major cornerstone of the government's energy security strategy," she said.
"The government must stop this overpriced, lumbering project and focus on cheaper, faster, reliable alternatives that will cut energy costs and fight climate change."
Prime Minster Boris Johnson recently said Sizewell C was "certainly on the agenda" and the government would be "bringing forward the plans as fast as possible".
The government has already committed £100m to Sizewell C and plans to take a 20% stake.
EDF, which already runs Sizewell B, will also take a 20% stake in the power station.