Bill Gates reportedly has his eye on the world’s first hydrogen-powered superyacht — a $644 million, environmentally friendly oasis on the sea with its own infinity pool, helipad, spa and gym.

The billionaire Microsoft co-founder was initially rumored to have already commissioned the 370-foot luxury Aqua yacht in a report Sunday in the UK paper The Telegraph.

However, the Dutch design firm Sinot insisted Monday that Aqua had yet to be sold to Gates, stressing it did not yet have a “business relationship” with the second-richest person in the world.

“We invite any visionary client to show their interest,” insisted the company — clearly aiming at eco-warrior billionaires just like him, with designer Sander Sinot saying the inspiration was “the lifestyle of a discerning, forward-looking owner.”

The vessel is powered by two 28-ton vacuum-sealed tanks cooled to minus-423 degrees Fahrenheit and filled with liquid hydrogen — with the only emission being water, according to the report. It will reach a top speed of 17 knots (19.5 mph) and be able to cross the Atlantic, the report says.

While far from the world’s largest yacht, plans show extreme luxury for the 14 guests and 31 crew members who can be accommodated.

It includes its own fully equipped gym, yoga studio, beauty room, massage parlor and a stunning outdoor infinity pool.

Along with luxurious bedrooms, there are numerous outdoor lounges, a giant spiral staircase and an amazing observation room at the front.

Gates’ main motivation in wanting to commission the yacht would be to signal his backing for new, clean technology to cut carbon emissions, the Telegraph said.

He regularly takes superyacht vacations — but usually rents yachts rather than owning his own.

Whoever buys it will not be able to enjoy it for a few more years, however, with the report saying Aqua will not be ready until 2024.

The Gates Foundation and Gates Ventures declined to comment to the Telegraph for its report.

“Aqua is a concept under development and has not been sold to Mr Gates,” Sinoit insisted.