Beijing will "reduce and remove" the 40% tariffs it places on US cars imported into China, US President Donald Trump has said, BBC reports.
China has not commented on President Trump's announcement, which he made on Twitter without providing details.
The move, if confirmed, would be welcomed by a car industry unsettled by the escalating US-China trade war.
President Trump and Xi Jinping have now agreed to a temporary truce in the bitter dispute.
Over dinner at the G20 summit, they agreed to not increase tariffs for 90 daysto allow for talks.
Failure to strike a deal would have seen tariffs on $200bn worth of Chinese goods rise from 10% to 25% at the start of next year, and would have opened the way for tariffs on additional Chinese goods.
On Monday, China's foreign ministry said the presidents of China and the US had instructed their economic teams to work towards removing all tariffs following the G20 meeting, Reuters reported.
Asian markets rallied after news of the trade war truce. In China, Hong Kong's Hang Seng index climbed 2.5% and the Shanghai Composite index jumped 2.6%. Japan's Nikkei 225 index rose 1%.
The gains spread to Europe, with the UK's FTSE 100 index, the Cac 40 in France and Germany's Dax index all up by about 2% in early trade.
The trade war has seen the US and China hit each other with escalating tariffs in an attempt to make their domestically made goods more competitive.
The US says its tariff policy is a response to China's "unfair" trade practices and accuses it of intellectual property theft.
Since July, the US has hit China with tariffs on $250bn (£195.9bn) worth of goods. China has retaliated with duties on some $110bn of US goods over the same period.