In an interview with CNBC on Monday, Bill Simon—who led the grocery giant from 2010 to 2014—said that “for the first time in a long time, there’s reason for the consumer to pause.”

“The consumer has had an incredible 10-, 12-year run…[but] we’re starting to see this accumulation of global macroeconomic issues, geopolitical issues, inflation, interest rates, loan repayments,” he explained.

Political division was also playing a part in dampening consumer sentiment, Simon added, noting that the “really contentious” 2024 presidential election and turbulence in Congress would pile up and make Americans wary of spending.

There was already evidence, he argued, that consumers’ habits were shifting.

“You can look back to Walmart’s last quarterly report; they talked about a very, very large trade down: Typically what you see during difficult economic times is a trade down from middle income to lower income and upper down to middle, and you’re starting to see that,” he said. “You also see shifts in things like pack sizes at the beginning of the month versus the end of the month: [Shoppers] buy larger-batch sizes in the beginning when they have more cash, and they buy smaller ones at the end of the month. All of that’s starting to rear its ugly head.”

End of the era of big bargains?

Meanwhile, there were subtle signs in the retail space that the era of big bargains was coming to an end, according to the ex–Walmart boss, who now serves on the boards of Darden Restaurants and HanesBrands.

“If you look at Amazon and Walmart’s [websites], there’s a lot of interesting things going on,” he told CNBC. “They usually say, ‘50-inch TV, $199,’ or something like that. And now they say, ‘50-inch TV, 40% off.’ You use percentages when you’re not real proud of your price point.”

Simon noted that lingering inflation was still forcing retailers’ prices upward.

“The retailers are feeling the inflationary push,” he said. “So that’s going to translate into consumers’ acceptance of the prices and what they buy.”

American consumers have helped the U.S. economy remain resilient over the past couple of years, with shoppers continuing to spend even in the face of sticky inflation, soaring interest rates, and recession fears.

Last week, Treasury Secretary Janet Yellen told Fortune that the surprisingly resilient consumer, coupled with a buoyant labor market, had blocked a recession.

Americans’ willingness to spend has created problems for the Federal Reserve, however, which has been tightening monetary policy in a bid to cool the economy and bring inflation closer to its 2% target.

As the question remains on whether consumers can maintain their pace of spending, some market watchers—like Walmart’s former exec Simon—believe that the tide may be turning.

Citigroup CEO Jane Fraser warned in a recent interview that “cracks” were beginning to show when it came to consumer spending, while researchers at McKinsey said in a report published last week that while consumer sentiment remained upbeat, Americans were spending more cautiously.

Meanwhile, economists at ING cautioned in a recent note that real disposable income in American households had dropped, noting that additional financial pressure would be piled on consumers with the restarting of student loan repayments.