DUBLIN Airport Authority (DAA) chairman David Dilger has resigned almost two years to the day since taking on the top job at the semi-state company.
Last night, the former Greencore boss told the DAA board of his intention to step down at the end of this month.
In a statement, the DAA, which manages the main Irish airports, said he is leaving to focus on other interests.
Dilger is a director of James Hardie International, a global construction supplies company, and is understood to be involved in business mentoring and early stage investments.
Transport, Tourism and Sport Minister Leo Varadkar said he regretted the resignation and thanked Mr Dilger for his work to date.
"I regret Mr Dilger's decision to stand down, and would like to thank him for his contribution as chairman since he was appointed in May 2009," he said. The Minister added that Mr Dilger's chairmanship coincided with a very difficult time for the company.
"He successfully steered the company through these difficult circumstances. He also oversaw the successful completion of Terminal 2, which opened on time and on budget. This achievement is a tribute to his time as chairman of the DAA.
"I would like to thank him for all his work for the DAA, and wish him well in his future endeavours."
In March Mr Dilger spoke out publicly against any proposals to split the country's three main airports into competing companies.
A decision on separation is due to be made later this year and the new minister has indicated his support for allowing Cork and Shannon airports some autonomy.
However, just this week Mr Varadkar admitted it would be difficult to break up the company at present given the debt levels at each of the airports.
The search for a replacement is expected to get under way immediately.
The DAA chairmanship has long been a plum job, often filled by politically connected business insiders.
Previous incumbents include Smurfit Kappa boss Gary McGann, one of the people present at the controversial dinner in July 2008 attended by Brian Cowen and then Anglo Irish Bank chief Sean FitzPatrick.
Prior to that Noel Hanlon, a Longford ambulance maker who was friends with Albert Reynolds, served as chairman of what was then Aer Rianta.
David Dilger is a former director of Bank of Ireland and Enterprise Ireland.