President Trump’s steep tariffs have started to weigh on consumers’ wallets, sending prices higher as the White House readies a more drastic — and potentially costly — expansion of its global trade war.

The risks in Mr. Trump’s economic strategy began to show on Tuesday, with the release of data that found inflation had accelerated in June. Prices rose noticeably on appliances, clothing and furniture, products that are all heavily exposed to the president’s taxes on imports from Canada, China and other major trading partners.

The inflation report undercut Mr. Trump’s continued assertions that Americans would not face financial repercussions from his increasingly aggressive trade brinkmanship. Since taking office, the president has imposed withering duties on allies and adversaries alike, with additional taxes on a range of products such as cars and steel.

The latest reading of the Consumer Price Index recorded the first signs of what economists had predicted all along, with U.S. businesses and consumers shouldering a growing share of the burden from the taxes Mr. Trump has imposed on imports.

The data also carried perhaps a new warning for the president as he prepares another round of tariffs on dozens of countries in about two weeks, including a 30 percent tax on the European Union. Some experts said that an uptick in inflation could foreshadow more significant price increases later, especially if Mr. Trump proceeds as planned.

“Up until this report, you could have argued that inflation is on a journey lower,” said Padhraic Garvey, who leads ING’s research team for the Americas. “Now we are on a journey higher.”