The nation's business establishment lashed out at Livedoor Co. on Wednesday, with both the head of the country's most powerful business lobby and the chief of the securities industry unleashing harsh words against the Internet startup.

Hiroshi Okuda, chairman of the Japan Business Federation (Nippon Keidanren), said Wednesday that the group's decision to admit Livedoor Co. was premature and a mistake.

"Depending on the outcome of the ongoing investigation by prosecutors, we will have no choice but to take certain measures," said the head of the nation's most influential business lobby, suggesting it might either expel Livedoor or ask it to leave.