Elon Musk announced that he has picked senior ad executive Linda Yaccarino as the CEO of Twitter on Friday.

In a tweet, Musk said he would remain in charge of design and technology at Twitter, with Yaccarino focusing primarily on business operations and turning Twitter into an "everything app" called X.

Musk tweeted on Thursday in the U.S.: "Excited to announce that I’ve hired a new CEO (chief executive officer) for X/Twitter. She will be starting in ~6 weeks!"

San Francisco-based Twitter was renamed as X Corp, according to Musk and court filings revealing a merger of the technology companies.

The entrepreneur, prior to buying the platform for $44 billion in October, revealed plans to turn it into "X, the everything app."

Musk said his role will transition to being executive chairperson and chief technology officer (CTO), overseeing product, software and sysops.

In a later tweet, he said, "The commitment to open source transparency and accepting a wide range of viewpoints remains unchanged."

It was in response to remarks from political commentator and producer Alex Lorusso, known on Twitter as Alx, that free speech on the platform remains a "top priority" for Musk "regardless of who the next" boss is.

Musk has previously joked that his dog Floki took over as chief executive.

It followed a tweet in December, just weeks after the takeover, saying: "I will resign as CEO as soon as I find someone foolish enough to take the job."

The pledge came after millions of Twitter users asked him to step down in a poll Musk created and promised to abide by.

He has had a tumultuous start to his journey at the platform, laying off about 80% of its 8,000 global staff and admitting it resulted in it losing a large amount of its functionality.

He also oversaw the scrapping of legacy "blue ticks," which verified a user’s identity, and were replaced by a paid-for subscription called Twitter Blue.

High-profile figures and celebrities said the move leaves the platform open to imposters and disinformation.

But Musk said the rules are "more about treating everyone equally" as there "shouldn’t be a different standard for celebrities."