Minister for Transport Noel Dempsey is under pressure to reveal what he knew about Aer Lingus's decision to drop its Shannon-Heathrow route.
Mr Dempsey has claimed that Aer Lingus told a Department of Transport official on June 13th that it was considering moving its Heathrow slots to Belfast but that he was not informed for a further six weeks.
Mr Dempsey took up his position as the new Minister for Transport on June 14th.
Labour transport spokesman Tommy Broughan expressed disbelief that when Mr Dempsey was briefed as the incoming minister on that day that he had not asked about Aer Lingus.
Mr Broughan suggested in the Dáil this afternoon that both Mr Dempsey and his predecessor Martin Cullen knew of a danger to routes from Shannon and possibly Cork and Dublin.
The Government has consistently claimed that it is cannot use its position as a shareholder to influence Aer Lingus's controversial decision to move its Heathrow slots from Shannon to Belfast.
Mr Broughan today questioned the claim and quoted from the company's 2006 annual report which said: "The board is responsible for overall group strategy including new activity and withdrawal from existing activities."
Mr Dempsey insisted the board power did not have the power to overrule managers.
"Even if the Government on its own or in combination with other shareholders called an egm [extraordinary general meeting], management of Aer Lingus is not obliged to follow any directions from shareholders," Mr Dempsey said.
When the Government appoints two new members to the Aer Lingus board they will "seek to ensure" they are informed about any decisions with implications for public policy, he added.
Fine Gael transport spokesman Fergus O'Dowd said Mr Dempsey statement about the future role of directors was an example of Government incompetence.
"The fact is you refused to appoint them [directors] when you could have and therefore when the whole issue of Aer Lingus was being discussed, two of the Government seats were vacant. There was nobody to articulate the policy for Shannon or for the region," Mr O'Dowd said.
He said it was utterly unbelievable "that everybody seemed to know" about the decision to move the route including the Dublin Airport Authority, the board of directors and the Department of Transport.
"But for 44 long days you sat in your department and nobody came in to tell you."
Earlier, Mr O'Dowd said Mr Dempsey and his predecessor, Martin Cullen, were either incompetent or negligent.
"In this instance it is much more credible that what we are witnessing is a cover-up," he said.
Labour Party Limerick East TD Jan O'Sullivan said it was "simply unbelievable" that Mr Dempsey had not been informed sooner and called for an independent inquiry.
Sinn Féin's Arthur Morgan said the Minister should make a statement to the Dáil explaining why the "entire Government was kept in the dark".
Opposition ire was stimulated by a written response yesterday to a parliamentary question by Fine Gael Limerick East TD Kieran O'Donnell which emerged late yesterday.
It said the Department made an inquiry about Shannon following a media report on June 13th saying the company was considering opening a base in Belfast.
"An official conveyed the concerns of the Department . . . about the implications for Shannon and asked the chief executive to give full consideration to the ways in which a new base might be accommodated before arriving at a decision, which he agreed to do. The matter was not brought to my attention," the Minister's response said.
The Minister said he became aware of Aer Lingus's intention on July 27th following a Department inquiry on a separate matter and arranged a meeting with Aer Lingus chief executive Dermot Mannion on August 3rd, five days before the public announcement of the move.