The European Commission is concerned over a new US accounting law that obliges all businesses listed there to present certified financial accounts, a spokesman said.
"There is a certain amount of concern, but we haven't decided yet if we are going to take the matter to the SEC," a spokesman for internal markets commissioner Mr Frederik Bolkestein said.
The Corporate Auditing Accountability law, signed into law in July, in theory applies to all companies irrespective of nationality.
The law, which comes into force this week, establishes an independent board to set standards and discipline auditors of public companies. Corporate executives will be required to accept responsibility for the accuracy and veracity of their companies' financial reports.
"The American authorities are quite aware that it is not in their interest to dissuade European companies from being registered in the US," the spokesman said.