TF International analyst Ming-Chi Kuo, who always appears to have his finger on Apple's pulse, said that the company was planning to "absorb most of the additional costs" of the tariffs.
The USTR action was published minutes after China's ministry of commerce said vice-premier Liu He conducted a call with US officials.
The Dow gained more than 400 points, or 1.7%, rising to 26,339 at 10:40 a.m.
The broader S&P 500 was up by roughly the same amount in percentage terms, while the tech-heavy Nasdaq fared even better, up 185 points or 2.35 per cent to 8,050.More news: Former id boss Tim Willits joins World War Z developer Saber Interactive
But the agency says it would delay the tariffs to December 15 on some goods, including cellphones, laptop computers, video game consoles, some toys, computer monitors, shoes and clothing.
But in a tweet on Tuesday, Mr Trump hinted that he was expecting something in return, suggesting that China's failure to "buy big" from USA farmers could be about to change. 1 "based on health, safety, national security and other factors". So far they have not done what they said.
According to lists published by the USTR, a broad category of items taken off a $200bn tariff list previous year will be subject to the 10% tariff as of 1 September.
The USTR's announcement comes amid growing concerns about a global economic slowdown.More news: Former NBA Point Guard Sebastian Telfair Sentenced 3.5 Years for Gun Possession
Remember when trade wars were "good and easy to win"? Previous tariffs were very targeted on some sectors, but the latest tariff move would have hiked prices on a wide variety of cheap consumer goods that USA shoppers buy from China en masse. "Products in this group include, for example, cell phones, laptop computers, video game consoles, certain toys, computer monitors, and certain items of footwear and clothing".
But it appears that the iPhone and other smartphones imported into the US from China are getting a short-term reprieve.
Trump had also personally criticized Chinese President Xi Jinping for failing to do more to stem sales of the synthetic opioid fentanyl amid an opioid overdosing crisis in the United States.More news: Sydney Stabbing Suspect Subdued With Milk Crate, Chairs