China’s government promised to respond to a U.S. proposal to tariff the rest of the goods it buys from China, raising the stakes for the dispute between the world’s two largest economies.

“The U.S. bullying and application of extreme pressure goes against multilateral trading rules,” Chinese Ministry of Commerce Spokesman Gao Feng said in Beijing on Thursday. “China is strongly opposed to such practices. If the U.S. persists, China will be forced to take necessary actions.”

Since trade talks in Washington ended with no progress last week, the two sides have stepped up their rhetoric and threats, with the U.S. announcing plans to tax nearly $300 billion of imports not already subject to punitive tariffs. China has said there can be no deal without the removal of all extra tariffs imposed since last year.

The Chinese government has no information about any U.S. plans to travel to Beijing to continue talks, Gao said. U.S. Treasury Secretary Steven Mnuchin said yesterday that he and chief negotiator Robert Lighthizer will travel to Beijing “at the appropriate time” but there are no plans as yet.

Gao refused to say whether Presidents Donald Trump and Xi Jinping would meet next month at the Group of Twenty meeting in Japan, directing that question to the Ministry of Foreign Affairs.