Britain gave the final go-ahead for the 38 billion pound ($51 billion) Sizewell C nuclear plant in eastern England on Tuesday after it secured investment from British and international investors including Canadian pension fund La Caisse.

Under the deal the British state will be the largest shareholder in the project with a 44.9% stake, La Caisse will hold 20%, UK energy firm Centrica 15% and London-headquartered Amber Infrastructure taking an initial 7.6%, joining France’s state-owned EDF which had already announced its 12.5% stake.

Britain needs to build new nuclear plants to replace its ageing fleet, boost energy security, reach its climate targets and create new jobs.

“Delivering next generation, publicly-owned clean power is vital to our energy security and growth,” finance minister Rachel Reeves said in a statement.

The announcement of La Caisse as the second biggest shareholder comes as a surprise after months of speculation that Canadian investor Brookfield was in pole position to invest.

Sizewell will be only the second new nuclear plant built in Britain in more than two decades, after French state-owned EDF’s Hinkley Point C. That has been beset by delays and cost overruns, and is not due to start operating until about 2030.

First proposed in the early 2010s, Sizewell C was originally going to be developed by EDF with China General Nuclear Power Group, but the UK government bought out the Chinese firm’s stake in 2022 amid security concerns.

France’s EDF has said it is investing around 1.1 billion pounds in Sizewell, while Centrica said in its statement it had committed to construction funding of 1.3 billion pounds.

The government statement said Britain’s National Wealth Fund would provide the majority of the debt finance for the project, alongside a debt guarantee from France’s export credit agency, Bpifrance Assurance Export.