Investors from China, America and the Middle East are said to be interested in a bid to build a new nuclear reactor on Anglesey.
Last month, Russian state-owned Rosatom was reported to be interested in buying Horizon Nuclear Power to build a replacement for ageing Wylfa reactors.
German owners E.ON and RWE npower have shelved the £8bn plan.
News agency Reuters has quoted industry sources saying other investors are also interested in Horizon.
Horizon is now up for sale, with the possibility that plans for Anglesey and Oldbury in Gloucestershire could still be pushed forward under new owners.
"There are five groups interested overall," said the source , who Reuters said had direct knowledge of the deals but who asked not to be identified.
"The preferred bidder will be the one who can take the site and build on it as fast as possible."
Early last month , Russian news agency Tass quoted the deputy head of Rosatom, Sergei Novikov, describing the British market as "very attractive" to the company.
At the time, a spokesperson for RWE npower said the reports were market speculation, and any moves to sell Horizon to any party were still at a very early stage.