The vast tariffs President-elect Donald Trump has promised to implement will likely lead to price increases at major American retailers like Walmart and Lowe’s, the companies’ chief financial officers said this week.

Walmart CFO John David Rainey told CNBC it is not yet clear which items would be affected.

“We never want to raise prices,” Rainey told the outlet Tuesday. “Our model is everyday low prices. But there probably will be cases where prices will go up for consumers.”

The company confirmed Rainey’s take in a statement given to Reuters: “We’re concerned that significantly increased tariffs could lead to increased costs for our customers at a time when they are still feeling the remnants of inflation.”

Lowe’s CFO Brandon Sink expressed a similar sentiment in a call with investors, according to Yahoo Finance.

“Roughly 40% of our cost of goods sold are sourced outside of the U.S., and that includes both direct imports and national brands through our vendor partners,” Sink said on the call, per Yahoo. “And as we look at potential impact, certainly would add product costs, but timing and details remain uncertain at this point.”

Trump repeatedly pledged on the campaign trail that he would lower runaway costs for American households by implementing tariffs, even though they typically make goods more expensive. He has proposed a tariff of up to 20% on all goods made in other countries and a special tariff of 60% for goods made in China.

Trump imposed tariffs using executive power in his first term, although his new proposal is much more extreme.

Electronics, toy and clothing are particularly susceptible to tariff-related price hikes, according to ABC News, given how these items often rely on imports.

It is not clear how quickly Trump plans to move forward once he retakes office, but American companies that rely on foreign imports are already preparing for the potential impact.