ASML Holding NV still does not have a permit to ship its most advanced lithography systems, needed to make advanced computer chips, to mainland China, its chief executive said on Wednesday, Reuters reported.

Peter Wennink, ASML’s chief executive, believes China is unlikely to replicate top-notch lithography technology on its own, as ASML relies on “relentless innovation” and some components can only be obtained from non-Chinese suppliers.

“I’m not saying no, because I know the laws of physics are the same in China as they are here,” he said, “Never say never. They will try.”

ASML, which has a near-monopoly on lithography, is not restricted from exporting its older technology to mainland China. In 2021, about $2.2 billion or 16% of ASML’s sales came from mainland China.

According to its most recent results, ASML reported fourth-quarter revenues of 4.986 billion euros, with sales of 1.6 billion euros (11.5 billion yuan) from 11 EUV lithography units.

For the year, ASML sold 42 EUV lithographs on revenues of 18.6 billion euros (133.9 billion yuan), accounting for 46 percent of sales of 13.6 billion euros (97.9 billion yuan). ASML also secured 26.2 billion euros (18.6 billion yuan) of orders in 2021, an increase of more than 200 percent year-on-year.