May 23 (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.