Plans for Britain’s first new nuclear power plant for a generation suffered a last-minute delay on Thursday night after Theresa May’s Government announced a new review.

Executives at French energy giant EDF were left surprised after ministers cast doubt on the plans by saying a decision on the Hinkley Point nuclear power station will not be made until September.

Both EDF and Government sources had thought that ministers would sign off the subsidy deal for the £18 billion plant today, after the board of EDF approved the project by 10 votes to seven.

However, within hours of EDF giving the project the go-ahead, Greg Clark, the new Business and Energy Secretary, announced that a final decision will now be delayed.

He said: “The UK needs a reliable and secure energy supply and the government believes that nuclear energy is an important part of the mix. The government will now consider carefully all the component parts of this project and make its decision in the early autumn.”