Elon Musk Tesla CEO
Tesla boss Elon Musk denies he lambasted employee for missing work event to witness birth of his child Reuters

Elon Musk has defended claims made by an upcoming book about him that he scolded a Tesla employee for missing a work event to be at the birth of his child.

The man behind PayPal, Tesla and SpaceX is claimed to have sent an email to the employee, saying: "That is no excuse. I am extremely disappointed. You need to figure out where your priorities are. We're changing the world and changing history, and you either commit or you don't."

A number of quotes painting Musk as an obsessed workaholic who will stop at nothing to succeed have been published by the Wall Street Journal ahead of the book's release on 21 May. Called Elon Musk: Tesla, SpaceX and the Quest for a Fantastic Future, the book is written by business and technology journalist Ashlee Vance.

'Total BS and hurtful'

Tweeting in defense of the comments, Musk told news website Vox.com: "I have never written or said this. Ashlee's book was not independently fact-checked. Should be taken w[ith] a grain of salt."

Musk tweeted again a few hours later, branding the book's claims as "total BS and hurtful," adding he would never tell an employee to miss his child's birth to attend a work meeting.

Vance reportedly spent 30 hours speaking to Musk while writing the book and interviewed 300 people to write it. The book's description says it was written with the help of "exclusive access to Musk, his family and friends."

The book is full of quotes from colleagues and associates of Musk who describe him as a man who worked 23 hours a day and told Tesla employees they could see their families when the company went bankrupt. Another quote, from Christie Nicholson, the daughter of an advisor to Musk, reads: "One night he told me, 'If there was a way that I could not eat, so I could work more, I would not eat. I wish there was a way to get nutrients without sitting down for a meal'."

During a spat with Ford, who threatened to sue Tesla over its use of the Model E name for an upcoming electric car, Musk recalls his feelings towards Ford boss Alan Mulally: "Like why did you go steal Tesla's E? Like you're some sort of fascist army marching across the alphabet, some sort of Sesame Street robber?"

Musk, who has been married three times and twice to the same woman, with whom he filed for a second divorce in December 2014, talks with Vance about finding the time to date. "I would like to allocate more time to dating, though. I need to find a girlfriend. That's why I need to care out just a little more time. I think maybe even another five to 10 - how much time does a woman want a week? Maybe 10 hours? That's kind of the minimum? I don't know."

Speaking to a potential investor, Musk is claimed to have said: "My mentality is that of a samurai. I would rather commit seppuku than fail," however he has since tweeted to deny this.