Three international banks have begun courting buyers for a 49% stake in Britain’s eight nuclear power stations, starting the process of a major shakeup of the sector’s ownership.

UK-listed Centrica said in February it was looking to sell its 20% stake in the nuclear plants, which UBS and Goldman Sachs are understood to be handling.

Industry watchers have speculated that majority owner EDF Energy, which is shouldering the huge financial burden of building Hinkley Point C in Somerset, also wanted to sell some of its stake.

The company, represented by Bank of America Merrill Lynch, is understood to have piggybacked on the sale after the British Gas-owner, Centrica, announced its plans.

The sale process has been dubbed Project Newton by insiders and is in the “very early stages”, a source close to the process told the Guardian. The banks’ involvement was first reported by SparkSpread.

State-owned China General Nuclear Power Group (CGN), which has a third stake in Hinkley Point C and wants to build its own reactors in Essex, has been named as a potential buyer.

The pool of possible buyers is a relatively small one, as private investors have generally steered clear of nuclear.

Aside from China, Japanese and South Korean nuclear firms could also be in the frame. Russia is another major nuclear power player, but ownership of UK plants would be politically unacceptable.

“You need an industrial player who is familiar with nuclear expertise. There are very few of these,” said one energy analyst, who did not want to be named.

Aside from one power station in Suffolk, the ageing nuclear plants are due to be retired in the mid-2020s.

Analysts have put the value of Centrica’s stake at £1.1bn, suggesting a sale of 49% could be worth more than £2.5bn. Even if a minority stake was sold, it is understood that EDF Energy would remain operator of the power stations.

EDF, Centrica and the banks declined to comment.