Watch out below.

Top U.S. business leaders are “bracing for a recession,” and many are already starting to slash costs to prepare their companies for a downturn ahead.

So says the research firm Gartner, after a study of all the recent fourth-quarter corporate results announcements, and the transcripts of business leaders’ earnings calls with Wall Street analysts.

The news comes just days after employers nationwide stunned Wall Street with dismal jobs-growth numbers for the month of February.

Meanwhile the Atlanta branch of the Federal Reserve, which tracks national economic numbers in real time, warns that the U.S. economy is already in danger of stalling.

“ ‘A significant number of leading firms are taking a recessionary stance and making preparations to capitalize on a downturn rather than be a casualty of one.’ ” — Tim Raiswell, Gartner

“Many of the world’s largest companies are starting to behave as if they are in a recession,” said Tim Raiswell, vice president of Gartner’s finance practice, in a published statement. “A significant number of leading firms are taking a recessionary stance and making preparations to capitalize on a downturn rather than be a casualty of one.”

Raiswell said that U.S. executives were still offering a “broadly positive” outlook for the economy. But more and more are talking about a possible “downturn” or “recession,” and have announced efficiency measures to cut costs.

That can’t be a positive development for a jobs market that generated just 20,000 new nonfarm jobs in February, a number far below economists’ consensus forecast.

Bank executives have sounded the alarm about the rise in risky consumer lending by nonbank providers, Gartner found.

And corporate leaders across the board are worried about the turmoil in Washington and a sharp slowdown in the Chinese economy, which is now the world’s biggest by some measures.

Donald Trump’s intermittent saber rattling against China over trade, along with the recent government shutdown and overseas problems like Brexit, are also factors.

Economists say that corporations dislike uncertainty more than almost any other policy scenario, because it makes it hard to plan. “[A]ll parties are largely guessing about the extent to which political rhetoric will become firm policy and what the impact will be on companies’ order books,” said Gartner’s Raiswell.

Wall Street economists think the economy is still on track to grow by about 1.5% this quarter. The New York Federal Reserve broadly agrees — although it has slashed that figure from the much healthier 2.4% predicted just six weeks ago.

But the Atlanta Fed, looking at the latest economic data, puts the figure at just 0.4% — barely above stalling speed. It believes that domestic private investment actually fell in the quarter, by somewhere between 2.4% and 2.9% in real terms.