The British government has moved closer to taking a stake in nuclear power generation for the first time in more than a decade after making an initial ￡100m investment in the planned Sizewell C power station in Suffolk.

The funding announced on Thursday is part of attempts by ministers to accelerate the project — led by France’s EDF Energy with China’s CGN as a minority partner — which has been plagued by delays as successive governments have struggled to find a funding model that would attract private finance.

The government said the ￡100m would help bring the Sizewell project to maturity and attract other external investors. It would work like a convertible loan, which would trigger once Sizewell C reaches its final investment decision, expected in three years' time.