China has "completely broken the agreement with us", claims Trump in a post on his social network Truth Social.
Trump did not elaborate on how it has broken the agreement, which was about reducing the tariffs that were shock-raised earlier this year in a trade war that took new momentum when Donald Trump began his second term.
The tariff reductions were to be applied when launched during a period to provide room for negotiations about the trade relationship between the world's largest and the world's second-largest economy.
Trump's statement caused the major indexes on the New York stock exchange to fall in pre-trading.
When the stock exchange had opened, the Dow Jones industrial index had fallen 0.1 percent after half an hour of trading, the broad S&P 500 had retreated 0.5 percent and the Nasdaq's technology-heavy composite index 0.8 percent.
