Ernst & Young has been barred from accepting new corporate audit clients for six months for failing to maintain its independence from a company whose books it audited.

The administrative law judge at the Securities and Exchange Commission also ordered the nation's third-largest accounting firm to pay $1.7 million in restitution, plus interest. The action on Friday was the first time the SEC had sought the suspension of a major accounting firm since 1975.

New York-based Ernst & Young said it did not plan to appeal the ruling, though it had previously argued its conduct was appropriate and met professional standards.

The SEC said the firm violated rules designed to keep accountants independent from the companies they audit when it engaged in a business deal with software maker PeopleSoft Inc.