US President Donald Trump on Friday threatened to impose a 25 percent tariff on Apple and other smartphone manufacturers unless their devices are made in the United States. Initially singling out Apple, Trump later expanded the warning to include all smartphone makers to ensure fairness.

"It would be also Samsung and anybody that makes that product, otherwise it wouldn't be fair," Trump said. He added that the tariffs would take effect by the "end of June."

While Apple designs its products in the US, the majority of iPhone assembly occurs in China, which remains at the center of an ongoing trade dispute with the United States. Apple has announced plans to shift some production to other countries like India, but Trump said this would not satisfy his demands. In a post on Truth Social, Trump wrote, "I had long ago informed Tim Cook of Apple that I expect their iPhones that will be sold in the United States of America will be manufactured and built in the United States, not India, or anyplace else."

"If that is not the case, a Tariff of at least 25 percent must be paid by Apple to the US," he added.

Trump’s latest statements echo remarks made during a recent trip to Qatar, where he told Apple CEO Tim Cook, "We're not interested in you building in India... we want you to build here and they're going to be upping their production in the United States."

Industry analysts say shifting iPhone production back to the US is unrealistic. Wedbush Securities analyst Dan Ives called the idea “a fairy tale that is not feasible,” noting that about 90 percent of Apple’s iPhone production and assembly still takes place in China despite some production moves elsewhere.

Apple’s stock price has dropped more than 20 percent since Trump took office, affected in part by his trade policies. Shares fell nearly 3 percent on Friday following the tariff threat.

Apple warned last month that the threatened US tariffs on Chinese goods, although temporarily eased for high-end tech like smartphones, could cost the company $900 million in the current quarter.

Analysts expect handset prices to rise if tariffs go into effect, putting pressure on consumers already dealing with price hikes on other goods.

The tariff threat comes amid a temporary 90-day truce in the US-China trade war, following an agreement last week to suspend tariffs on each other’s goods.