The world's two biggest economies are on the brink of an economically destructive trade war. Here's what experts think could happen next.

U.S. President Donald Trump this week shut a trade loophole that has been used to ship low-value packages duty-free from China, the "de minimis" exemption on import tariffs. Trump's halt to Section 321 de minimis is part of his implementation of an additional 10% tariff on China and 25% tariffs on Canada and Mexico,

China’s tariff increases and other countermeasures were mostly symbolic and apparently designed to project strength while leaving the door open to talks.

Oil extended declines after China imposed levies on some US commodities, with West Texas Intermediate falling to around $72 per barrel and the global benchmark Brent hovering near $75. The yuan traded offshore extended losses with regional peers, while gold was little changed

As China and the U.S. battle over tariffs, locked in a tussle that could result in a deal or a trade war between the world's two largest economies, staying away from China's stock market is becoming the default option for foreign investors.

China put export controls on tungsten and other niche metals used in the electronics, aviation and defense industries as it retaliated in a targeted way to US tariffs.

Canada and Mexico both conceded to Trump's demands over border security and drug trafficking, earning a pause on tariffs. It's unclear if China plans to do the same.