A final investment decision on the site, to be built near the Sellafield nuclear complex, is due in 2018.
"There is a universe of options open to us," Nugen said.
"We are talking to potential investors familiar with the nuclear industry, including banks, credit-export agencies and nuclear companies in countries interested in nuclear new build projects," a Nugen spokesperson told the BBC.
Moorside is designed to provide up to 3.8 gigawatts of power - compared to 3.2 gigawatts at Hinkley Point. It is expected to employ up to 21,000 workers over the lifetime of the project and provide enough power for 7% of the UK's electricity requirements when the reactors are switched on in the mid 2020s.
The three reactors would be provided by Westinghouse, the US subsidiary of Toshiba which supplies about half of the world's operating nuclear plants.
Nugen hopes to tap into the existing infrastructure at Sellafield, which employs more than 10,000 staff and is probably the largest concentration of nuclear expertise in the world.