The US is delaying imposing tariffs on some imports from China until 15 December because of "health, safety, national security and other factors".
The products include mobile phones, laptops, video game consoles, some toys, computer monitors, and certain footwear and clothing.
The surprise news from the United States Trade Representative office sparked a rally in share prices.
Other items facing a 10% tariff will go ahead as planned on 1 September.
US President Donald Trump, speaking to reporters, said that the delay was in part to avoid hitting US shoppers this Christmas.
The USTR's announcement was released minutes after China's Ministry of Commerce said Vice Premier Liu He had conducted a phone call with US trade officials.