Adds ASML statement in paragraphs 3 and 7

June 18 (Reuters) - U.S. Commerce Secretary Howard Lutnick has told ASML ASML.AS that Washington is concerned that one of its top chipmaking machines may have found its way to China in violation of U.S.-led export restrictions, Bloomberg News reported on Thursday.

Lutnick expressed the concerns over ASML’s extreme ultraviolet lithography, or EUV machines, to senior leaders of the Dutch firm in a series of meetings, the report said.

"ASML has never shipped an EUV machine to China nor have we shipped to China any component, module or equipment specially designed to be used in an EUV machine," the chipmaker told Reuters in an emailed statement.

ASML's most advanced EUV systems are roughly the size of a school bus and weigh 180 tons.

The U.S. Commerce Department and the White House were not immediately available for comment outside business hours when contacted by Reuters.

In April, Washington proposed a law requiring U.S. allies to align with its export controls to curb China’s ability to make advanced semiconductors, with equipment made by ASML named in the legislation.

ASML said it has refuted allegations regarding non-compliance with export controls concerning China, adding that it has "consistently adjusted its business to any development in export controls to comply to any new rules."

Reuters reported in December that Chinese scientists have developed a prototype of an EUV machine that was built by a team of former engineers from ASML, an effort described as China's version of the Manhattan Project.