Celebrities threaten to leave Twitter as Elon Musk confirms he wants to start charging verified users

Celebrities and public figures have threatened to leave Twitter, as Elon Musk floats a monthly fee for verified users.

Twitter users who sport a "blue tick" could soon have to pay $US20 ($31) for the privilege, as the Elon Musk Twitter takeover continues. 

READ MORE: Instagram trying to reconnect users locked out of accounts

Profiles that have a blue checkmark next to their name usually represent a public figure, such as movie stars, celebrities, businesses, politicians and journalists. 

Author Stephen King tweeted on Monday he'd leave the social media platform if Musk implemented this change.

"$20 a month to keep my blue check? F— that, they should pay me," King tweeted, telling his near 7 million Twitter followers it was about the "principal", not the money.

Musk replied, defending the incoming subscription service - asking King if lowering the monthly amount from $20 to $8 would keep him. 

"We need to pay the bills somehow! Twitter cannot rely entirely on advertisers," Musk said.

The new Twitter owner said he would explain more soon and described the measure as the "only way to defeat the bots and trolls". 

The original Wonder Woman, Lynda Carter, also took a swipe at Twitter with a photo of her before and after Twitter verification.

It's not yet confirmed when the change to the Twitter Blue subscription will come into force.