The Public Company Accounting Oversight Board begins deliberations today on whether to draft rules that would restrict accounting firms from providing their audit clients with tax services.

Regulatory direction and public remarks by members of the Board and the Securities and Exchange Commission have hinted for months that accounting firms should brace themselves for the possibility. The Big Four firms have declined to discuss the issue at this stage. A PricewaterhouseCoopers spokesman said simply, “I don’t think we will be in a position to comment until after the PCAOB issues its draft rule.”