President Donald Trump called China's rare earth export controls a 'bad moment' as both countries navigate tensions over critical defense materials, and potential tariff increases.

It aims to extract trade concessions from President Donald Trump and ensure the world remains dependent on China for critical raw materials.

Since the start of this year, dozens of scientists and researchers have left US institutions to take up full-time roles in China. This so-called “reverse brain drain” trend is not new, but comes amid a push from the Trump administration to cut federal research funding and as China aims to boost its global science and technology standing.

In a post on social media, President Donald Trump also raised the possibility of canceling a planned meeting with Chinese leader Xi Jinping later this

Prices for several minerals have surged in recent months. Germanium, used in semiconductors and optics, has spiked amid reduced Chinese exports, while antimony trioxide prices have nearly doubled year-over-year. Car manufacturers have also struggled to obtain rare earths following China’s export curbs.

The United States and China on Tuesday will begin charging additional port fees on ocean shipping firms that move everything from holiday toys to crude oil, making the high seas a key front in the trade war between the world's two largest economies.