After more than a year of will-he-or-won't-he speculation, billionaire Elon Musk appears finally ready to pull the plug on the longtime San Francisco headquarters of the tech company formerly known as Twitter.

The social media platform X Corp. is expected to permanently close its corporate hub at 1355 Market St. in the city's Mid-Market area, a move Musk confirmed as the result of frustrations in operating in San Francisco and elsewhere throughout California. The Market Street office will be shut "over the next few weeks," according to an internal email sent to employees on Monday. News of the closing was reported earlier by the New York Times.

"No choice," Musk said in a Monday post on X about the closing. "It is impossible to operate in San Francisco if you’re processing payments."

San Francisco-based X employees are expected to be moved to the Silicon Valley area, either to an existing office the company leases in San Jose or to an engineering-focused hub in nearby Palo Alto that it will share with xAI, a Musk-controlled artificial intelligence startup.

“This is an important decision that impacts many of you, but is the right decision for our company in the long term,” X CEO Linda Yaccarino wrote in the email to employees.

Musk took X private after acquiring the company for $44 billion nearly two years ago. In the aftermath of Musk’s acquisition, he made substantial cuts to the social media platform’s workforce. The company employed about 1,500 people across the globe at this time last year, according to Securities and Exchange Commission filings, a fraction of the 7,500-person workforce it had in late 2021. Its employee base in San Francisco is currently estimated to be a little more than 100 people.

The impending closure lands a couple of weeks after the mercurial tech mogul said he would relocate X's headquarters to Austin, Texas, as well as his aerospace company, SpaceX, from California to Texas in moves he said were in opposition to a new California law banning school districts from requiring schools to notify parents if their child asks to change their gender identification.

Musk has been a vocal critic of San Francisco and California politics. He has repeatedly commented on concerns such as homelessness, crime and the rising costs of doing business in the state, and has long threatened to substantially downsize or altogether shut down real estate holdings across his multiple companies.

Still, Musk last year said he had no plans to relocate X out of the San Francisco Bay Area despite what he called the market's "doom spiral," saying that some people "expect X will move too. We will not. You only know who your real friends are when the chips are down. San Francisco, beautiful San Francisco, though others forsake you, we will always be your friend.”

In addition to X and SpaceX, Musk is also the head of electric car maker Tesla, which relocated its headquarters from California to Texas prior to the billionaire's 2022 acquisition of what was then known as Twitter.

X leases about 458,000 square feet for its headquarters at 1355 Market St., where it has been based since 2012, according to CoStar data. The company has been trying to sublease a substantial portion of its space in the building, but it is not clear how much or whether X will instead pay a termination fee to landlord Shorenstein Properties to officially sever its obligations.

Musk and a representative for X did not respond to CoStar News' requests for comment. A spokesperson for Shorenstein declined to comment.

The looming vacancy comes at a time when San Francisco's office market finally appeared to be regaining its footing. Slammed by ongoing remote work and a slew of high-profile tenant downsizings, the city has been trying to recover from a record amount of available sublet and direct space. San Francisco's vacancy rate hit a high of more than 22.5%, according to CoStar data, and while there has been an uptick in leasing activity, tenants are still giving back far more space than they're taking on.