The mountain and the barren surrounding valley, in Logar province, a two-hour drive from the capital, contain one of the world’s biggest untapped reserves of copper.

China is negotiating with Taliban authorities to start mining at the site, called Mes Aynak, according to Chinese and Taliban officials. Beijing is also in talks to begin work on oil-and-gas reserves in the north of the country, Amu Darya. Both projects were on hold for years because of the war, which ended when the Taliban seized power in August.

Dozens of Chinese mining companies have descended on Kabul in recent weeks seeking contracts for other mines.

U.S. officials say they are concerned that China will fill the vacuum left by the American withdrawal from Afghanistan. Beijing developed a relationship with the Taliban in recent years and kept its Kabul embassy functioning when Western missions fled the Taliban takeover.