"We're having a little squabble with China because we've been treated very unfairly for many decades," President Trump told reporters at the White House.
To recoup the same profit on each iPhone sold as before, Apple would need to increase iPhone prices by a similar amount.
Trump, who began the standoff last year complaining about unfair Chinese trade practices, has specifically blasted the WTO for slighting US trade interests to the benefit of China.
Beijing might cut Boeing orders as well as purchases of US farm products.
Beijing managed to keep Chinese economic growth steady in the most recent quarter despite a drop in exports to the United States.
Trump's combative stance, highlighted by the new round of import tariffs imposed this week, has upended decades of cautious statecraft in the West aimed at forcing China to join the global order.
The new increase applies to an even greater value of goods put at about USD 300 billion.
India under pressure after US Commerce Secretary Wilbur Ross said that New Delhi must lower duties on a range of products to help American biz
Despite the negotiations, Trump, at times, has threatened to increase tariffs on Chinese products, but has backed down his warning amid signs of progress towards finalising a new trade agreement.
The US on Friday increased punitive duties on $200 billion in imports from 10 to 25 per cent, prompting China's commerce ministry to repeat its pledge to take necessary measures.
US duty hike on $200 billion Chinese imports to exacerbate uncertainty in global trade: Moody's Investors Service
The US Friday increased tariffs on import of USD 200 billion Chinese products from 10 per cent to 25 per cent.
The Federal Communications Commission on Thursday said that because of China Mobile USA's ownership and control by the Chinese government allowing it may threaten national security.
Forex traders said the US President Donald Trump on Sunday threatened to raise tariffs on USD 200 billion worth of Chinese goods and this in turn impacted investor sentiment in the currency market.
Indian exports to China jumped 31 per cent to $17 billion in FY 2018-19. The surge in exports was mainly due to greater demand for marine products, grapes, raw cotton and plastic raw materials.
Last week, negotiators from both the countries met in Beijing to resolve the nine month-long trade war.