In a memo to employees on Thursday, Chris Cox, Meta’s chief product officer, echoed Mr. Zuckerberg’s sentiments and said the company was in “serious times” and that economic “headwinds are fierce,” according to a copy of the memo that was read to The Times.

As a result, Meta has posted back-to-back profit declines this year, the first time that has happened in over a decade. In February, after a dismal financial report, Meta’s stock plummeted 26 percent and its market value plunged more than $230 billion in what was the company’s biggest one-day wipeout. In March, the company told employees that it was cutting back or eliminating free services like laundry and dry cleaning.

The company is also dealing with a blow to its advertising business after Apple made privacy changes to its mobile operating system that limit the amount of data that Facebook and Instagram can collect on its users.

That economic uncertainty is hitting as Meta navigates tumult in its core social networking and advertising business. Mr. Zuckerberg declared last year that his company, which was renamed Meta from Facebook, was making a long-term bet to build the immersive world of the so-called metaverse. 

In an internal meeting this week, Mr. Zuckerberg said the tech giant was facing one of the “worst downturns that we’ve seen in recent history.”

 Mark Zuckerberg has a message for Meta employees: Buckle up for tough times ahead. At an internal meeting on Thursday, Mr. Zuckerberg, the chief executive of Meta, said the Silicon Valley company was facing one of the “worst downturns that we’ve seen in recent history,”

according to copies of his comments that were shared with The New York Times. He told Meta’s 77,800 workers that they should prepare to do more work with fewer resources and that their performances would be graded more intensely than previously.

Mr. Zuckerberg added that the company — which owns Facebook, Instagram and other apps — was lowering its hiring targets. Meta now plans to bring on 6,000 to 7,000 new engineers this year, down from a previous goal of around 10,000, 

he said. In some areas, hiring will pause entirely, especially of junior engineers, though the head count will increase in other parts of the business,

The C.E.O.’s comments, which were some of the most sharply worded ones he has made to employees, reflect the degree of difficulty that Meta is facing with its business. The company, which for years went from strength to strength financially, has been in an unfamiliar position this year as it has struggled.