US President Donald Trump warned that he was ready to slap tariffs on virtually all Chinese imports into the United States, threatening duties on another $267 billion in Chinese goods on top of $200 billion in imports now primed for levies in coming days, according to Reuters.

The moves would sharply escalate Trump's trade war with Beijing over his demands for major changes in economic, trade and technology policy.

China has threatened retaliation, which could include action against US companies operating there. Hours after a public comment period closed on his $200 billion China tariff list, Trump told reporters aboard Air Force One that he was "being strong on China because I have to be".

"The $200 billion we are talking about could take place very soon depending on what happens with them. To a certain extent its going to be up to China", Trump said. "And I hate to say this, but behind that is another $267 billion ready to go on short notice if I want. That totally changes the equation."

The $200 billion list, which includes some consumer products such as cameras and recording devices, luggage, handbags, tires and vacuum cleaners, would be subject to tariffs of 10 percent to 25 percent. Mobile phones, the biggest US import from China, have so far been spared, but would be included if Trump activates the $267 billion tariff list.

Trump has been disappointed that China has not caved into his threats so far and the trade war has not done anything other than hurt US businesses.