March 31 (Reuters) - Hut 8 said on Monday it had joined hands with President Donald Trump's son, Eric Trump, to launch a bitcoin mining company called American Bitcoin.

Miami, Florida-based Hut 8 merged the majority of its mining operations for an 80% stake in American Data Centers, a company formed by a group of investors including Eric Trump and Donald Trump Jr. that has been relaunched as American Bitcoin.

The move illustrates the growing involvement of the Trump family in the crypto landscape as the industry moves towards mainstream acceptance.

President Trump has promised to be the "crypto president," who will popularize its mainstream use in America.

U.S.-listed shares of Hut 8 briefly soared 27% in premarket trading. They have fallen 42.8% so far this year as of last close.

"From the start, we've backed our conviction in Bitcoin -personally and through our businesses," Donald Trump Jr. said.

"But simply buying Bitcoin is only half the story. Mining it on favorable economics opens an even bigger opportunity."

American Bitcoin will mainly focus on bitcoin mining while building a strategic bitcoin reserve. The company will be led by CEO Matt Prusak, with Eric Trump serving as the chief strategy officer.

In the longer run, American Bitcoin plans to be publicly listed to expand its access to capital.

The carving out of the mining business will narrow Hut 8's focus on lower-volatility energy and digital infrastructure company.

Hut 8 will serve as American Bitcoin's exclusive infrastructure and operating partner.