The threat of further escalation in the trade war between the world's two largest economies has loomed large over financial markets and the global economy for much of the year, and investors initially greeted the ceasefire with relief.
The ministry said that China would try to work quickly to implement specific items already agreed upon, as both sides "actively promote the work of negotiations within 90 days in accordance with a clear timetable and road map".
That gives the president 24 hours to fix the damage inflected when the market plunged nearly 800 points on Tuesday after a series of tweets from Trump suggested a trade war with China could resume next year.
The two leaders said they would hold off on imposing additional tariffs for 90 days starting December 1 while they seek a solution to their beefs over trade.
China could be preparing to spring a global compact to drive tariffs to zero, and approach Trans-Pacific Partnership (TPP) members including Australia for access to the grouping, positioning Beijing as a champion for free trade.
Additionally, China was said to be beginning to buy products from United States farmers "immediately".
But Asia failed to follow the lead to the same extent after China gave its first official comments on the temporary trade truce which allowed for tariff hikes to be postponed for 90 days- until 1 April.
When asked about structural changes the United States had made as a prerequisite to any trade deal, Mnuchin said he expected some things to be implemented "on a rolling basis" in phase two.
Mr Trump said this week on Twitter that Beijing had agreed to "reduce and remove" tariffs the 40% tariffs it places on U.S. cars.
In Buenos Aires, Trump agreed to delay the scheduled US tariff increase for 90 days while the two sides negotiate over the administration's complaints related to how Beijing systematically steals trade secrets and forces the USA and other foreign countries to hand over sensitive technology as the price of admission to the vast Chinese market.
"Reaching an agreement within three months is a spur to not only China, but also the U.S. If the two sides fail to reach a deal, all the White House promises will be invalid", it said. "I am a Tariff Man", Mr. Trump said in a series of tweets.
"China will start with the implementation of the specific matters in which consensus has been reached, the sooner the better", it added, without providing more details.
"Ninety days is very little time to fix these perennial issues", said Bill Adams, senior economist at PNC. Trump's National Economic Council advisor Larry Kudlow tried to strike an update note while acknowledging to Fox News a deal "hasn't been signed and sealed and delivered yet".
Trump applauded the news in a tweet.
"Ultimately, I believe, we will be making a deal - either now or into the future", he wrote. Seven of the top 10 vehicle models manufactured in the USA and exported to China previous year were made by BMW and Mercedes-Benz. Fentanyl, mixed in with heroin, has caused a spike in drug overdoses in the U.S. Instead of being hammered out by lower-level officials, he said Xi came very prepared for the conversation, and that the deal was mostly done by the two leaders.
One of the few automotive stocks to score a gain on Tuesday was Tesla which only recently began work on a new factory in Shanghai that eventually will let it sidestep the tariff battle.
Trump added China would roll back tariffs of 40 percent on cars, though Beijing has yet to confirm the move.
In return, China agreed to buy what the White House called a "not yet agreed upon, but very substantial" amount of USA products to help narrow America's gaping trade deficit with China.