Trump Media & Technology is merging with fusion energy company TAE Technologies in a deal worth more than $6 billion. 

TAE, which is privately owned, is developing technology aimed at producing energy by fusing atomic nuclei. Trump Media & Technology owns President Donald Trump's Truth Social platform.

Former California lawmaker Devin Nunes, now chief executive of Trump Media, will serve as co-CEO of the new company with TAE Technologies CEO Michl Binderbauer, according to a statement from the two companies Thursday.

The merger comes amid a difficult year for Trump Media shares, which trade under the ticker DJT — the same as Mr. Trump's initials. Through Wednesday, the stock was down 69% for the year, even as the S&P 500 had gained 14%.

After the merger was announced Thursday morning, Trump Media shares jumped $2.25, or 21%, to $12.72 in pre-market trading. 

The combination represents "a major play on creating the first public nuclear fusion company in the U.S.," Wedbush Securities analyst Dan Ives said in a report. TAE's investors include Google, Chevron and Goldman Sachs, he noted.

TAE has "safely built and operated five fusion reactors and importantly proven major energy and fusion breakthroughs over the years... putting TAE at the top of the mountain in the fusion global scene in our view," Ives said.

Fusion power will prove to be "the most dramatic energy breakthrough since the onset of commercial nuclear energy in the 1950s," Nunes said in a statement.