(Reuters) -Restricting the sale of extreme ultraviolet (EUV) lithography equipment to China is the "single most important export control" the United States has in the area of semiconductors, the White House's AI and crypto czar David Sacks said on Friday.

"The first Trump administration began the restriction, and it's of paramount importance that it continues," Sacks wrote on X.

Dutch company ASML makes EUV chipmaking machines, which produce the most sophisticated semiconductors.

Lithography systems use beams of light to help to create the chip circuitry. ASML's first generation of EUV systems, currently used to make most chips in smartphones and AI chips, use light in the "extreme ultraviolet" wavelength to create design features down to 13 nanometres in resolution, smaller than a virus.