Twitter owner Elon Musk said overnight Sunday that his social media platform will retire its widely recognized blue bird logo, and eventually the Twitter name, as part of his relentless effort to overhaul the company.

Amid tweets asking users whether the brand should change its default color from blue to black or white, Musk added: "Soon we shall bid adieu to the twitter brand and, gradually, all the birds."

Musk said he would replace the famed bird with an "X," which would match his early payment processing company X.com and the recently named parent company of Twitter, X Holdings. Musk has spoken repeatedly of his hopes to make Twitter part of an "everything app" that would include a payment system as well as communications.

"If a good enough X logo is posted tonight, we'll make go live worldwide tomorrow," Musk tweeted. He later added, "I like the letter X." He suggested putting the ideally "Art Deco"-style logo against a black backdrop, teasing such an image in a picture and short video.

Later on Sunday, he tweeted that the interim logo "goes live later today."

Musk's announcement caught Twitter employees as well as users by surprise. At midday, the company's webpage on branding still declared: "Our logo is our most recognizable asset. That's why we're so protective of it."

In later tweets, Twitter chief executive Linda Yaccarino declared that "X is the future state of unlimited interactivity," including payments and the buying and selling of "goods, services, and opportunities" that will be "powered by AI."

Branding experts and former employees, including some Musk elevated before dismissing, were openly critical of the decision.

"Looking forward to Elon stans explaining to me how destroying a universally-recognizable brand is a smart business decision," tweeted marketing entrepreneur Ben Parr, president of Octane AI.

Ex-head of product Esther Crawford tweeted: "Corporate seppuku: destroying your own product or brand. Usually committed by new management in pursuit of cost-savings due to a lack of understanding about the core business or disregard for the customer experience. The result is a massive loss of shareholder value."

The identity change would follow other radical changes Musk has pushed through since buying the global conversation platform for $44 billion in October.

Musk has gotten rid of about three-fourths of Twitter's staff, thrown out past rules against organized disinformation campaigns and personally engaged with accounts previously suspended for hate speech.

To drive more users to pay $8 a month for a premium experience that includes wider distribution and the ability to edit tweets, Musk has imposed new limits on the regular interface, most recently paring back the ability to send direct messages.

The Pew Research Center reported in May that a quarter of Twitter users said they did not expect to be using the platform in a year, further reducing the value of advertising.

A rebrand will probably make such a separation easier for those on the fence.

"I've been reluctant to leave Twitter entirely, but I have to tell you I won't have a problem leaving X," tweeted Hugo Award-winning science fiction author John Scalzi, a power user who has tweeted more than 170,000 times.

Katie Hart, a U.K. consultant on the neuropsychology of marketing, said the long-standing Twitter logo and branding benefited from the natural associations of birds and tweeting.

"It appears as though Elon Musk is simply moving his organization even further down the road of cold, hard functionality, instead of the softer associations it currently has," Hart said by email. "It will give many users a very clear and constant visual reminder about the changes which are occurring on the platform, which may encourage more to leave and move their allegiance elsewhere."

Musk's new policies have amplified hate speech, misinformation and extremism and have driven users and advertisers away, according to multiple studies and surveys. Attacks on gay and transgender people and ethnic minorities have surged. Propagandists for multiple countries have purchased the new check marks, making their voices louder.

Musk has called such reports distorted, and Yaccarino said last week that "more than 99% of content users and advertisers see on Twitter is healthy" and that hate speech is being seen less often.

But Musk recently acknowledged that ad revenue is down about 50 percent under his tenure and that the company still has negative cash flow.

The chaos at Twitter has provided an opening for new challengers, most notably Threads, recently launched by Facebook and Instagram owner Meta. Threads attracted more than 100 million users in less than a week, though the number of active daily users has since fallen sharply.

Musk has dismissed Threads as a threat, arguing that the relaxed rules on Twitter make it a better place for tough conversations.

"Frankly, I love the negative feedback on this platform. Vastly preferable to some sniffy censorship bureau!" Musk tweeted amid his posts about the branding change.

Analysts have different means for estimating the true worth of a brand, and many different firms put out varying lists of the most important in the world.

One report by consultancy Brand Finance said that Twitter fell out of the top 500 this year.