China has warned Washington that it will retaliate if the US goes ahead with the levies. President Donald Trump has already imposed tariffs totaling 20% on Chinese shipments since his second term started in January. The US is also set to complete a review this week of Beijing's compliance with the phase-one trade deal struck during Trump's first term. China reported data last week that showed profits at industrial firms contracted at the start of the year, flashing a worrying sign for the economy.