Alcoa Corp., the largest U.S. aluminum producer, said it will stop selling products to Russian companies and halt raw-material purchases from the country in response to the invasion of Ukraine.

The decision makes Alcoa one of the world’s first major aluminum makers to shun Russia. Although the war on Ukraine has no direct impact on Alcoa’s business, Chief Executive Roy Harvey on Tuesday told investors the Pittsburgh-based company was assessing what to do about aluminum sales to Russian companies.

“We are deeply troubled by the invasion of Ukraine, which has caused devastating loss of life. Our hearts break for all Ukrainians who are suffering from this unprovoked conflict,” Harvey wrote in a letter to employees. “In response to the current aggression, Alcoa will cease buying raw materials from, or selling our products to, Russian businesses.”

So far, sanctions haven’t singled out the Russian aluminum industry, which is one of the world’s largest suppliers of the metal. The Biden administration is holding off for now on direct sanctions against Russian aluminum, which could disrupt already short global supplies, Bloomberg News reported last week, citing people familiar with the matter.

Russian exports of industrial metals are sinking as buyers and financiers shy away, according to executives and analysts tracking trade flows. The global aluminum market swung to a 1.9 million-ton deficit last year, according to the World Bureau of Metal Statistics.