The Chinese units of the "Big Four" accounting firms said on Thursday they intend to appeal a ruling that could suspend their operations in the United States for six months. They promised their services to clients won't be interrupted.

The firms' joint statement followed a ruling on Wednesday by Cameron Elliot, an administrative law judge with the US Securities and Exchange Commission, involving the Chinese units of Deloitte Touche Tohmatsu Ltd, Ernst & Young, KPMG and PricewaterhouseCoopers LLP.

Elliot recommended that the four be barred from providing audits for US-traded companies for six months. They had rejected the US regulator's demand for access to audit documents.