Wylfa was home to a much smaller nuclear power station which operated from 1972 to 2015 with an output of one gigawatt (GW). Wylfa B, the new station, is expected to eventually generate 3.2 GW of electricity – more than three times the output of its predecessor.

Its output would likely be similar to Hinkley Point C in Somerset, which has been under construction for several years, and the Sizewell C power station where construction has just started.

Construction of both plants is being overseen by EDF, the French state-owned power company, which this week confirmed it wanted to bid for Wylfa B too.

The site could eventually also include one or more small modular reactors (SMRs), potentially creating the UK’s biggest centre for nuclear power generation.

A second site at Oldbury on Severn in Gloucestershire is expected to be designated for more nuclear developments, most likely based around SMRs, according to Whitehall sources.

Ms Coutinho said: “We are powering ahead with the biggest expansion of nuclear energy in 70 years.

“Anglesey has a proud nuclear history and it is only right that, once again, it can play a central role in boosting the UK’s energy security.”

Prime Minister Rishi Sunak and Ms Coutinho announced ambitions to build a third large nuclear power plant in January as part of a new nuclear roadmap. The plans will see Britain’s nuclear power generating capacity increase up to fourfold by 2050.