The Financial Reporting Council's professional oversight board said all banks incorporated in Britain could now face an in-depth review of their accounts for the business year just ended.

The board's audit inspection unit selects a sample of "major" audits from across sectors each year for in-depth checks but criteria used in the past meant not all banks would face a possible inspection.

"The board continues to have regard to the level of public interest involved and has determined that the level of current public interest in banks means that these should be included as a separate category," Barbara Mills, chair of the Oversight Board, said in a statement.

"The challenges of the recession still present heightened audit risks in a number of areas and the audit inspection unit will continue to have particular regard during 2010/11 to those risks," Mills said.

In the 2008-09 financial year the unit checked about 100 major audits of which 30 percent were from the financial services sector. This percentage is expected to rise following Monday's announcement.

The inspection unit will pay particular attention to revenue recognition and fraud this time round and continue to look at "going concern" issues, fair value accounting and compliance with ethical standards, all key issues for banks in light of lessons from the financial crisis.