Tightening the noose around the audit companies having arrangements with global firms, the accounting regulator ICAI has sought details of their tie-ups with MNCs to check surrogate practices.

The decision to seek tie-up details from CA firms, especially those associated with the Big 4-- PWC, Ernst & Young, KPMG and Deloitte--follows a report by an Institute of Chartered Accountants of India (ICAI) committee on the multi-crore Satyam scam.

"The details are required pursuant to a meeting held with the ministry of corporate affairs in regard to the public image about auditor's role, manner in which surrogate firms hold out to the public, use of international brand name and host of other related issues," the ICAI said.

Surrogate practices refer to foreign firms carrying out auditing functions in the country through clandestine arrangements with domestic firms.