Shares of rare earth and base metal mining companies in the United States surged on Thursday after China tightened export restrictions, sparking market speculation that the Trump administration would more aggressively invest in building a domestic supply chain.

US rare earth stocks rose by 15%, with Newcorp Development shares up about 12%, Ramaco Resources over 11%, Energy Fuels more than 9%, and MP Materials over 2%. Albemarle shares increased by about 5%, Trilogy Metals by around 4%, and Lithium Americas by about 2%.

Beijing now requires foreign entities to obtain a license to export products containing rare earth metals valued at 0.1% or more of the goods’ value, according to the Chinese Ministry of Commerce. Companies will also need export licenses if they use Chinese magnetic extraction, refining, or recycling technologies.

An official from the US administration told CNBC, “The White House and relevant agencies are conducting a thorough assessment of any impact of the new rules, which were announced without prior notice and imposed in a clear attempt to control technology supply chains worldwide.”

China imposed these restrictions ahead of an expected meeting between President Xi Jinping and President Donald Trump on the sidelines of the Asia-Pacific Economic Cooperation summit in Seoul, South Korea, later this month.

Rare earth metals are a major sticking point in trade talks between Beijing and Washington. China dominates the global rare earth supply chain, while the US depends on imports from China.

The White House and the US critical minerals industry have accused China of market manipulation to push foreign competitors out. Rare earth metals are a subset of critical minerals essential for US weapons platforms, robotics, electric vehicles, electronics, and other applications.

In July, the US Department of Defense struck an unprecedented deal with MP Materials, the largest US rare earth mining company, including a stake in its shares, marking the first major move by the Trump administration to support the US industry against China. The White House later acquired stakes in Lithium Americas and Trilogy Metals, fueling investor speculation of more deals.

A US Defense Department spokesperson commented on the Chinese export restrictions: “This action reinforces the need for a proactive US industrial policy.” They added, “Building resilient supply chains is a matter of economic and national security.”

Neither MP Materials nor USA Rare Earth and Energy Fuels have made deals with the White House, but their CEOs told CNBC they are in close contact with the Trump administration.