Gallium and germanium and their chemical compounds will be subject to export controls meant to protect Chinese national security starting 1 August, China's Ministry of Commerce said.

Exporters for the two metals will need to apply for licenses from the commerce ministry if they want to start or continue to ship them out of the country and will be required to report details of the overseas buyers and their applications, it said.

According to the UK Critical Minerals Intelligence Centre, the move could put the brakes on the electric vehicle and semiconductor industry as China accounts for about 94 per cent of the world's gallium production.

Practically though this is more of an annoyance, the metals aren't particularly rare or difficult to find, but China's kept them cheap. Both metals are byproducts from processing other commodities, such as coal and bauxite. With restricted supply, higher prices could draw out production from elsewhere.

Analysts think that China has to be careful with this move because it could lose market dominance if it plays the game too long. The same has happened in other things like antimony, tungsten and rare earths."