The NBA begins its playoffs with the Play-In Tournament anElon Musk has decided not to join Twitter's board, the company said on Sunday, less than a week after the billionaire Tesla CEO disclosed he is the social media company's largest shareholder and was offered a seat.d continues with the full eight first round series of games.

Musk's appointment was set to become official on Saturday, but he told Twitter that morning he would not join, Twitter CEO Parag Agrawal tweeted late on Sunday.

Agrawal did not say whether Musk had given a reason for the reversal. He noted that the board appointment was contingent on a background check as well as a formal acceptance by Musk.

"I believe this is for the best," Agrawal said in a note to staff shared in his tweet. "We have and will always value input from our shareholders whether they are on our board or not. Elon is our biggest shareholder and we will remain open to his input."

"There will be distractions ahead," he continued, but urged staff to "tune out the noise."

Shortly after Agrawal's announcement, Musk tweeted an emoji of a face with a hand over its mouth. He didn't reply to a request for comment.

The Tesla and SpaceX CEO is a prolific Twitter user but has also become an increasingly vocal critic of the platform in recent months.

 He's criticized the way the company enforces its rules about what people cannot say on the platform, suggesting it has failed to "adhere to free speech principles," and has asked whether it should make its algorithm open source.