Britain is phasing out coal plants and investing in renewables to help meet its climate targets. But many of its nuclear plants - another source of low-carbon electricity - also need replacing, and progress so far has been mixed.
Japan's Hitachi on Wednesday dropped its plans to build a new nuclear plant in Britain, while Japan's Toshiba Corp, scrapped its British NuGen project in 2018 after its U.S. reactor unit Westinghouse went bankrupt.
"The government is looking at options to invest in Sizewell, nuclear energy has a key role in meeting our net zero commitments," Johnson's spokesman told journalists.
"We regularly engage with all developers on their projects and are considering a range of financing solutions."
EDF is building Britain's first new nuclear plant in more than two decades, Hinkley Point C, with backing from China's CGN. It also hopes to build Sizewell C, in which CGN also owns a 20% development phase stake.
EDF has called on the government to launch a new regulated asset base (RAB) funding model to help more projects get built, which could see British households pay through their electricity bills while the plants are still being constructed.
Proponents say the model, previously used in Britain to finance monopoly infrastructure assets such as water, gas and electricity networks, would ultimately lower the cost of new projects for consumers.
However, critics say it will leave taxpayers liable for any cost over-runs and delays during construction.
Britain's nuclear power plants can supply around 20% of the country's electricity demand, but around half the plants are set to close in the next four years.
(Reporting by Elizabeth Piper, additional reporting by Susanna Twidale; editing by Sarah Young and Mark Potter)