China says products made by US memory chip giant Micron Technology are a national security risk.
The country's cyberspace regulator announced that America's biggest maker of memory chips poses serious network security risks.
It is China's first major move against a US chip maker, as tensions increase between Beijing and Washington.
The announcement is the latest development in a deepening row between the US and China over the technology crucial to economies around the world.
The long-running dispute has seen Washington impose a series of measures against Beijing's chip-making industry and invest billions of dollars to boost America's semiconductor sector