One of the top behind-the-scenes figures in Fine Gael has quit his veteran role after revelations he was paid thousands of euro by a charity to lobby the Government.
Party strategist Frank Flannery has also stood down from his long-standing senior position within the disabled charity Rehab.
In a statement, Mr Flannery said he resigned from Rehab because of the controversy it has sparked.
"It is a step that I undertake with real regret but I have come to the opinion that my involvement with the board is making the Rehab Group the subject of political controversy as this time," he said.
Also confirming his resignation as director of elections and trustee of Fine Gael, he added: "My involvement with Fine Gael related only to electoral strategy and organisation and I had no role in advising the government."
Mr Flannery, a central figure in the senior coalition party for decades, had been under pressure to appear before a powerful parliamentary watchdog to answer questions about his pay and perks as a director of Rehab.
The Public Accounts Committee (PAC) also wanted to quiz him about his business dealings, links to a company Eco Solutions, as well as reports he was paid large sums of money by Rehab to lobby the Fine Gael-led government.
A close advisor to leading Fine Gael figures, Mr Flannery said the party and Taoiseach Enda Kenny would continue to have his complete support as "a private citizen and as a proud ordinary member of Fine Gael."
He made no reference to repeated calls for him to appear before the PAC, and his resignations from both Fine Gael and Rehab will cast doubt on whether he can be compelled to attend.
Mr Flannery worked for Rehab for 34 years and was a former chief executive of the charity, which has come under intense scrutiny recently - not least about the salary of its current chief executive Angela Kerins.
Several senior Government figures had urged him to co-operate with the PAC.
Sinn Fein deputy leader Mary Lou McDonald, a member of the parliamentary committee, insisted Mr Flannery should come before TDs to answers outstanding questions.
"The one thing missing from Frank Flannery's statement this evening is the looming question of whether or not he will appear before the Public Accounts Committee," she said.
"Politicians from all parties, including the Taoiseach and Tanaiste, have said he must appear before the committee.
"His statement this evening does not change that. He must come before the committee and address the issues of public concern that currently surround him."
Fine Gael general secretary Tom Curran said Mr Flannery's positions within the party were voluntary.
"Frank has, over a period of more than four decades, served Fine Gael in a variety of roles," he said, confirming his resignation.
"I have thanked him for his unstinting and loyal service to the party, especially in helping to rebuild the Fine Gael organisation over past 12 years.
"I wish him all the best in the future."
PAC revealed it had written to Rehab earlier today about Mr Flannery appearing before it.
Fianna Fail's John McGuinness, PAC chairman, said he still expected him to "co-operate fully" with the parliamentary watchdog and to give evidence in the coming weeks.
"The position of the Committee in respect of Mr Flannery has not changed and, like the former board members at the Central Remedial Clinic, I expect that Mr Flannery will want to appear before the Committee to clarify issues in relation to the Rehab Group," he said.
Mr Flannery's evidence would be "central" to its inquiries which began with a cross examination of Ms Kerins and other senior Rehab figures last month, Mr McGuinness said.
"It was clear during that meeting that the witnesses present were not in a position to fully answer the questions of the (PAC) members and, therefore, a second opportunity will be available to Rehab to answer questions on areas such as remuneration, the involvement of Rehab with Complete Eco Solutions Limited - a company in which Mr Flannery was a shareholder - and in relation to the expenditure under the charitable lotteries fund," he said.
"The committee expects to receive a comprehensive set of documentation in the coming days from Rehab and the committee will consider that documentation at its meeting on Thursday, March 13."
Mr McGuinness said other revelations about Mr Flannery over the past week will also have to be dealt with.
Speaking in Manchester, Mr Kenny said he had not spoken to Mr Flannery today.
He said: "I don't want to personalise this but Frank Flannery has been around since the time of the late Garret FitzGerald and had been always been an important part of the development of Fine Gael in all its phases over the years.
"I know of the comment and statement he's issued now and I do hope that he's made his decision here, which is clear, and which is strong, I think.
"Obviously, I would understand that if he were to get an invitation from the Public Accounts Committee that he should cooperate with that committee as everybody else should as well.
"I think, in the interest of the charities, which are so important to Irish people all over the world, that it's very fundamental that there be transparency, accountability, and access and cooperation."
Mr Kenny agreed he went "back a long way" with Mr Flannery.
He said: "This is not the way that you would expect things to be but I think in the interests of the work that he has done himself, both in regard to the Fine Gael party and also to his many long years being associated with the Rehab people, h e's made his decision now and I respect him for that."