Under pressure from the U.S. government, the Dutch government has withheld granting a licence for ASML to export the machines, which are considered "dual use" goods with possible military applications.

CEO Peter Wennink said he thought it unlikely that China would be able to replicate top lithography technology independently because ASML relies on "relentless innovation" and integrating components that are only available from non-Chinese suppliers.

"I am not saying it cannot be done, because I know the laws of physics are the same in China as they are here," he said. "Never say never. They will certainly try."

ASML, which has a near monopoly in the lithography market, is not restricted from exporting slightly older technology to China, the world's largest consumer of semiconductors.

Around $2.2 billion, or 16%, of ASML's sales went to China in 2021, making it the company's third biggest market by geography, behind Taiwan and South Korea. The company forecasts Chinese sales at a comparable level in 2022.

(Reporting by Toby Sterling, Editing by Louise Heavens and Jan Harvey)