According to the Times, the Saudis recently approached Musk and offered to buy even more Tesla shares, an offer that Musk refused.
Tesla Inc shares jumped more than 7 percent on Tuesday after Chief Executive Elon Musk said on Twitter he is considering taking the electric vehicle maker private at $420 per share as it goes through a period of rapid growth and financial constraints.
$420 per share would be a significant premium on where Tesla is now trading, and also its performance over the first half of the year.
The stock had been worth about $342 a share before Musk's tweet.
Tesla did not respond to a request for comment immediately.
There Is an Absolutely Gigantic Rogue Planet Wandering Our Galactic Neighbourhood
If you were to stand on it (not a good idea) you'd be subjected to temperatures in excess of 1,500 degrees Fahrenheit. The unusual object, called SIMP J01365663+0933473, has a magnetic field more than 200 times stronger than Jupiter's.
Tesla's stock spiked Tuesday after Musk made the abrupt announcement in a terse tweet.
Separately, the Financial Times reported on Tuesday that Saudi Arabia's sovereign wealth fund, overseen by Crown Prince Mohammed bin Salman, has built an undisclosed stake of 3-5% in Tesla.
But it was not clear how seriously to take the post, given Mr Musk's history on the social media service.
The tweets have added to speculation about Tesla, which is spending heavily as it ramps up production of its latest auto, the Model 3.