US stocks linked to rare earth metals and other critical minerals gained this week, getting a boost from signs that the Trump administration will favor a sector that’s become a flashpoint in the trade standoff between the US and China.

Rare-earth magnet player USA Rare Earth Inc. jumped 70% in the short trading week. TMC The Metals Company Inc., a Vancouver-based company that’s seeking permission from the US to gather critical metals at the bottom of the ocean, gained 52%.

Shares of MP Materials Corp., a miner and refiner of rare earth elements, rose 16% this week in their best performance since September — even after giving up some of the week’s gains when the company halted shipments of rare earth concentrate to China as a result of Chinese tariffs on imports.

All three soared on Monday after the Financial Times reported over the weekend that the Trump administration is planning an executive order to enable the stockpiling of critical metals found on the floor of the Pacific Ocean. The US was responding to China’s efforts to limit exports of its own rare earth supplies. MP Materials and USA Rare Earth jumped again on Wednesday after Trump launched a probe into the need for tariffs on critical minerals.

“The moves that they’re making would suggest that they understand that we have to build out our supply chain here,” Steven Schoffstall, director of ETF product management at Sprott Asset Management, said of the Trump administration. “If you want to tariff something, presumably you want to build up that industry within the US borders, and the hope there is that investment will follow.”

The actions have become a central part of the escalating trade tension between Washington and Beijing. China is the dominant producer of metals that are vital to making crucial products like computer chips, nuclear reactor rods and fighter planes, and Beijing appears to be using that position to push back against Trump’s tariffs. As Washington looks to boost domestic production, Trump’s trade probe could cover all minerals defined as critical by the United States Geological Survey, a list that includes rare earth elements alongside other materials like lithium, cobalt and zinc.

Rare Earth USA is building a magnet factory in Oklahoma that’s scheduled to come online commercially next year, and it owns a rare earth deposit in Texas where it plans to extract ore for its own facility and other sectors such as the defense industry.

MP Materials, meanwhile, bills itself as the sole fully-integrated producer of rare earths in the US, with capabilities ranging from mining and refining to magnet manufacturing.

“In recent days, manufacturers across critical industries have urgently reached out in search of a secure, resilient source of materials and magnets,” the company said in a statement on Thursday. “We are uniquely positioned to answer that call”

TMC aims to gather nodules from the seabed that contain metals such as cobalt and nickel used in electric vehicle batteries. Its move to seek approval from the Trump administration has drawn condemnation from an organization affiliated with the United Nations that regulates the commercialization of deep sea resources.

Trump’s moves have made the three stocks winners even as his trade war has punished broader markets. TMC and MP Materials are up double digits since Feb. 19, a period that’s seen the S&P 500 Index fall 14%. Rare Earth USA shares have been volatile since the firm went public last month by merging with a special-purpose acquisition company, but they’ve more than doubled this month.

Uranium miners including Energy Fuels Inc. and Uranium Energy Corp. notched their own advances on Wednesday, after uranium was included in Trump’s trade-probe order. Energy Fuels jumped again Thursday when it said it had developed technology to produce most of the rare earth compounds subject to new Chinese export curbs.

Despite the indications that mining companies will be favored by the administration, Trump’s trade war presents complications. MP Materials said Thursday that selling its materials under the steep levies that Beijing has imposed is “neither commercially rational nor aligned with America’s national interest.” The company also cited Chinese export controls as a reason to halt shipments. MP’s shares fell 4.5% on Thursday.

US tariffs also threaten to raise costs for parts of the supply chain that remain outside the country. For rare earths, opening new mines in the US could take years, while new processing facilities may have a hard time competing with long-running international ones, Benchmark analyst Subash Chandra said.

“Once you sort of unthread it all, there is no clear line of sight of a non-Chinese feedstock through a non-Chinese processing facility to the end user,” Chandra said. “If we say we’re going to penalize everything that’s not American, yes there’s a benefit to these companies, but there’s also cost to these companies.”