Mr. Musk did not name the new chief executive. In a tweet, he said “she will be starting in ~6 weeks!” He added that he would still oversee Twitter’s product and software as “CTO” — chief technology officer.
Mr. Musk did not provide other details and did not respond to an emailed request for comment. In the past, he has made promises about what he would do at Twitter and his other companies that he has not followed through on.
Mr. Musk, who bought Twitter for $44 billion last year, will retain a firm grip on the company whether he names a chief executive or not. As Twitter’s owner, he has put his stamp on it by eliminating more than 75 percent of its 7,500 employees, installing his own leaders and changing the service’s features and strategy. He also took Twitter private, which means he does not have to disclose corporate information to the public.
Mr. Musk raised the idea of a chief executive for Twitter in December after he was criticized for some of his decisions at the company. He ran a poll on Twitter at the time asking if he should step down as the head of the company. “I will abide by the results of the poll,” he wrote.
More than 17 million votes were cast in the poll, with some 58 percent of respondents saying they were in favor of him stepping down as chief executive. In February, while speaking at a conference in Dubai, Mr. Musk said he was aiming to name a new Twitter chief executive by the end of 2023.
Twitter’s workers were not notified of a new chief executive before Mr. Musk’s tweet, according to two employees.
Any new chief executive is set to inherit a litany of challenges at Twitter. The company faces a sagging advertising business, which has been its main source of revenue, as well as debt payments of about $1.5 billion a year from the sale to Mr. Musk. At an investor conference in March, he said Twitter had experienced a 50 percent decline in ad revenue and had been on the path to bankruptcy within months.
Last month, in an interview with the BBC, Mr. Musk said that most of Twitter’s advertisers had returned.
Mr. Musk has also been under pressure from investors at his other companies — notably the electric carmaker Tesla — to move away from day-to-day management of Twitter, which they have regarded as a distraction. Shares of Tesla, which were little changed for most of the day, jumped after Mr. Musk’s tweet, rising about 2 percent in the final minutes of trading on Thursday.
Mr. Musk has previously ceded some leadership responsibilities at his other companies. At SpaceX, his private rocket manufacturer, he has delegated much of the running of the firm to Gwynne Shotwell, the president and chief operating officer. That has freed Mr. Musk to focus on engineering and product decisions, and to move among his various companies.