China’s cancellation of tax relief on exports has left the aluminum industry scrambling to assess the impact on supply flows, with Chinese companies suffering steep stock declines while their international peers rally.

Aluminum soared as China announced it was removing a tax rebate that covers over 5 million tons of exports of the metal.

Soaring demand for copper will require $250 billion of investment over the next decade, helping to drive further mergers in the industry, BHP Group Ltd. chief executive officer Mike Henry said.

Harmony Gold, South Africa’s biggest gold producer by volume, said on Thursday it had appointed Beyers Nel as chief executive officer to take over from Peter Steenkamp, who is retiring.

China needs to deploy more economic stimulus if copper demand is to revive, according to a major importer of the metal.

Australian miner Rio Tinto said on Wednesday it had approved the construction of a new 25-megawatt (MW) solar plant at its Kennecott copper operation in Utah, bringing the mine’s total solar capacity to 30MW.

Using more aluminum and recycled copper would help China cope with scarce copper resources, an industry group said on Wednesday, at a time when tight copper concentrate supplies are eroding profits at Chinese smelters.

Chinese copper smelters are facing pressure to rein in an expansion that’s pounding the industry’s profitability. The viability of plants across the globe may be at stake.

MMC Norilsk Nickel PJSC, Russia’s biggest miner, is in advanced talks to build a large copper smelter on China’s south coast, according to people familiar with the situation.

China has reduced its exposure to the US economy since Donald Trump’s first administration, leaving it better placed to weather the punitive trade tariffs being pledged by the president-elect, according to Robert Friedland, the founder of Ivanhoe Mines Ltd.