Shares of General Motors (GM) are in the spotlight on Wednesday after the company announced plans to produce electric vehicle drive systems and motors known collectively as "Ultium Drive," challenging Tesla's (TSLA) dominance of the clean-energy car market to date. Meanwhile, GM CEO Mary Barra has recently said that the automaker had done "appropriate diligence" before signing a deal with Nikola (NKLA) and that questions swirling around Nikola "should be referred to Nikola." Barra's comments followed a short report by Hindenburg Research calling GM's partner "an intricate fraud" built on "dozens of lies."

ULTIUM DRIVE: General Motors' next-generation EVs are expected to be powered by a family of five interchangeable drive units and three motors, known collectively as "Ultium Drive," the company has announced. "Ultium Drive will help the company transition its current portfolio to a fully electric lineup, providing significant advantages over GM's previous EVs in performance, scale, speed to market, and manufacturing efficiencies. Ultium Drive combines electric motors and single-speed transmissions to apply power - generated by Ultium battery cells - to the wheels of GM's upcoming electric vehicles. GM will lead the design and development of Ultium Drive's modular architecture," announced General Motors.

Ken Morris, GM vice president, Autonomous and Electric Vehicle Programs, added: "Making motors, transmissions, driveline components, and systems are among GM's best-known competencies, and our manufacturing expertise is proving not only transferable but advantageous as we make the transition to EVs."

'APPROPRIATE DILIGENCE': At Monday's RBC Capital Markets Global Industrials Conference, GM CEO Mary Barra confirmed that the automaker had done "appropriate diligence" before signing a deal with Nikola and that questions swirling around Nikola "should be referred to Nikola."

The comments followed a report by short-selling research firm Hindenburg Research saying it believes Nikola "is an intricate fraud built on dozens of lies over the course of its Founder and Executive Chairman Trevor Milton's career." The firm argued that it has "gathered extensive evidence-including recorded phone calls, text messages, private emails and behind-the-scenes photographs-detailing dozens of false statements by Nikola Founder Trevor Milton," adding that it has "never seen this level of deception at a public company, especially of this size."

Nikola has since denied Hindenberg's claims and said it has hired a law firm to evaluate legal recourse over the allegations. "To be clear, this was not a research report and it is not accurate. This was a hit job for short sale profit driven by greed," Nikola said in a statement. It added that it intended to bring the actions to the attention of the SEC.

The accusations came days after the company announced a 10-year alliance with General Motors. Under the terms of the agreement, GM will engineer and manufacture Nikola's Badger pickup truck and provide its Ultium battery system and Hydrotec fuel-cell technology for Nikola's semi-trucks in exchange for an 11% stake in the company valued at $2B.

On Tuesday, the Financial Times and Wall Street Journal each separately reported the Justice Department has joined securities regulators in probing allegations that Nikola Corp. (NKLA) misled investors by exaggerating claims about its technology

PRICE ACTION: In morning trading, shares of General Motors have gained about 1% to $31.77, while Tesla's stock has dropped almost 1% to $447.01. Shares of Nikola have advanced over 1% to $33.20.