President Donald Trump is chiming in on Apple's sales warning from earlier this week, an announcement that prompted a quick drop in the iPhone maker's stock price.

"They're gonna be fine," Trump said Friday at a White House news conference. "Apple is a great company."

In a letter to investors Wednesday, Apple CEO Tim Cook said revenue in the company's fiscal first quarter would be lower than expected, a rare occurrence from one of the most valuable and profitable companies in the world. Apple shares fell 7 percent to $147 in trading after the market close on Wednesday. Shares fell another 9.5 percent to $142.88 on Thursday morning, before rebounding 1.6 percent to $144.52 in early Friday trading.

Trump said Apple's stock price has gone up "hundreds of percent" since he's been president, but added that he wants the company to make its iPhone and other products in the US. 

"Don't forget this: Apple makes their product in China," Trump said. "I told Tim Cook, who's a friend of mine who I like a lot, 'Make your product in the United States. Build those big, beautiful plants that go on for miles, it seems. Build those plants in the United States.'...China is the biggest beneficiary of Apple, more than us, because they build their product mostly in China."

Neither Apple nor the White House immediately responded to requests for comment.