Central Bank of Ireland
A fifth high profile official, Fiona Muldoon, has announced her resignation from the Central Bank of Ireland during 2013 (Reuters)

The long list of resignations from the Central Bank of Ireland continued as the official responsible for supervising all credit institutions across the country stepped down.

In statement posted on the CBI website, Fiona Muldoon said she was stepping down in May 2014 after being in her post for two and a half years.

"I joined the Central Bank of Ireland on my return to Ireland, at a time of great challenge for the financial services industry and for the country. It has been a privilege to work with so many others on the pressing economic and regulatory issues of the day," she said.

"I hope I have made a meaningful contribution towards resolving some of those challenges and to the Bank during my time here. I would like to wish the Governor, the Deputy Governor and all of my colleagues every continued success in their on-going efforts to restore the financial services regulatory landscape in Ireland," she added.

Her announcement comes after the chief executive of the Irish unit of insurance giant RSA, Philip Smith, resigned amid a probe into the firm's accounting practices.

Governor Patrick Honohan, in charge of the CBI, said Muldoon had been a key player in reforming the financial system through establishing better regulations in Ireland during the country's economic crisis.

"Fiona brought great leadership strengths and practical knowledge of the financial services industry to the role. She has been instrumental in many of the initiatives undertaken by the Bank to address the role of the regulator, the mortgage and SME arrears issues and the stabilisation of the banking sector.

"She has made a significant contribution to the development and implementation of our prudential regulatory strategy in the Banking, Insurance and Credit Union sectors. I would like to thank her for her service and wish her well in the future."

Muldoon is the fifth heavyweight resignation from the CBI over the course of this year.

Previously financial regulator and deputy governor Matthew Elderfield left to take up a job in London with Lloyds Banking Group in compliance.

Similarly, chief economist Lars Frisell resigned to take up a post at the International Monetary Fund (IMF) after being appointed to the CBI in June 2012.

Jonathan McMahon and director of enforcement Peter Oakes also left their positions over the course of the year.