Donald Trump is now imposing a 104% tariff on goods imported from China after the country did not withdraw its retaliatory tariffs on the US.
As the additional levies, which came into force this morning, were announced, US stocks reacted by slipping into negative territory, The Times reports.
While acknowledging his tariffs had been "somewhat explosive", Trump insisted they were bringing in $2billion every day to the American economy.
China has said it will "fight to the end" in the trade war, while the White House remained confident a trade deal would eventually be struck.
Press secretary Karoline Leavitt told reporters: "The Chinese want to make a deal. They just don’t know how to do it."
Almost 70 countries around the world have approached the US for talks over trade deals.