Tesla CEO, Elon Musk  has revealed that the company will start shipping its long awaited Semi Truck  prime mover later this year, followed by its Cybertruck pick-up in 2023.

Musk has said previously that both the Semi and the Cyber would be in production next year.

Musk, who offloaded $US6.9 billion worth of stock in Tesla to accumulate cash ahead of a trial that could force him to follow through on an agreement to acquire Twitter, is renowned for making bold statements and setting difficult deadlines. Many of the arbitrary deadlines Musk has set in in the past have been missed without explanation.

The much hyped Semi Truck  was first announced in 2017 and was originally intended to make its sales debut two years later in 2019.

Musk, who  still owns almost 15 per cent of the electric auto maker, said that he was done selling and would now start buying Tesla shares if the Twitter deal doesn’t close.

“In the hopefully unlikely event that Twitter forces this deal to close and some equity partners don’t come through, it is important to avoid an emergency sale of Tesla stock,” Musk said.

Musk has now dumped about $US32 billion worth of Tesla shares since last November.

Musk, who is estimated to be the world’s richest person, said less than four months ago he had no further stock sales planned and has attempted since then to terminate his $US44 billion acquisition of Twitter. The social media company has since sued to force Musk to go through with the deal, and a trial is scheduled for October.

“He is cashing up for Twitter,” said Charu Chanana, a strategist at Saxo Capital Markets in Singapore, who believes Musk may be trying to take advantage of Tesla shares rebounding about 35 per cent since late May.

“The bear market rally has started to falter, and further repricing of Fed expectations could mean more pain for equities ahead, especially in tech.”

Musk’s $250.2 billion fortune is the world’s largest, according to the Bloomberg Billionaires Index, though his wealth has shrunk by about $20.1 billion this year as Tesla’s stock declined.

The automotive maker’s shareholders approved a three-for-one stock split last week, a move designed to attract an even larger number of retail investors.

Tesla’s better-than-expected second-quarter earnings have been a tailwind, along with landmark U.S. legislation that includes tax credits for electric car purchases and loans to companies constructing plants that make clean vehicles.