China’s exports of natural graphite, a material used in electric vehicle batteries, have rebounded from a low hit in December, when Beijing imposed controls to tighten its grip on the supply of minerals vital to advanced manufacturing.

Overseas sales rose to 6,275 tons in January and 10,722 tons in February, according to the latest Chinese customs data. Volumes in December had plunged to 3,973 tons. China’s exports averaged about 17,000 tons a month in the year through October, suggesting that the government’s drawn out approvals process continues to impede trade flows. 

The export restrictions are generally viewed as Beijing’s response to trade barriers raised on Chinese products by Western nations. The curbs were announced just days after the US stepped up efforts to keep advanced semiconductor chips out of China. 

And tensions are ratcheting up. The Biden administration is considering blacklisiting a number of Chinese semiconductor firms linked to Huawei Technologies Co., after the telecom giant notched a significant technological breakthrough last year, according to people familiar with the matter.