Fianna Fail deputy leader Dara Calleary objected to being appointed as Government Chief Whip during a tense meeting with newly elected Taoiseach Micheál Martin.
However, Mr Calleary was forced to accept the role as he was the last Fianna Fáil TD called to Government Buildings and Mr Martin had already allocated all his ministries.
The long-serving Mayo TD told colleagues he was furious about the appointment but was left with no option but to accept the position as Mr Martin had no other ministries to offer by the time Mr Calleary was called to the Taoiseach's Office.
Ministers who were appointed on Saturday afternoon said the Fianna Fail deputy leader was "visibly angry" when they gathered in Government Buildings before returning to the National Convention Centre to be voted into office.
Mr Martin's decision to appoint Mr Calleary as Chief Whip has been described by his party colleagues as an "appalling snub".
The move also lead to accusations that the new Government is ignoring vast areas of rural Ireland by failing to appoint a senior minister in Connaught or the North West.
Fine Gael were also blindsided by the decision as they expected Mr Calleary to be given a ministry, which would mean the west is represented at Cabinet by a senior minister. Fine Gael did appoint Galway West TD Hildegarde Naughton as a super junior minister responsible for roads.
In a statement, Ms Naughton described herself as the Government's "most senior minister in the West of Ireland".
However, she is a Minister of State and does not have full Cabinet responsibility or oversight of a government department.
The newly elected Government has come under sustained criticisms over the lack of representation for people living beyond the Shannon and along the west coast at Cabinet.
Yesterday, ministers were forced to deny rural Ireland was being left behind by the new Government.
Agriculture Minister Barry Cowen insisted the full roster of ministers has still to be decided and said the new Government will ensure "no region in Ireland is left behind".
Climate Minister Eamon Ryan said: "I don't think Government can ignore any part of the country", but admitted it is "difficult to get geographic spread" in a three-party coalition.
Fianna Fáil and Fine Gael are expected to appoint ministers of State from the regions in the coming days to ensure there is a better geographical spread of ministers. However, Mr Martin and Tanaiste Leo Varadkar only have seven position to appoint and are faced with difficult choices after dozens of TDs were left disappointed after the Cabinet was announced.
A senior Fine Gael source last night said there "will be more people disappointed than promoted" when the next round of ministries is revealed.
Mr Martin will have a major battle on his hands dealing with the fallout from his Cabinet appointments.
Yesterday, long-serving TDs were angry over the Taoiseach's appoint of first-time deputy Norma Foley as Education Minister and former Social Democrat leader as Health Minister. However, there was fury across the party over the appointment of Mr Calleary as Chief Whip rather than a full Cabinet Minister.
The Government Chief Whip is paid the same as a minister of State (€134,976) which is more than €40,000 less than a Cabinet minister (€175,699).
A senior FF TD said it was an "absolute disgrace" that the party's deputy leader was the last to be called to Mr Martin's office on Saturday.
One TD said people from across the west were calling and texting complaining about the decision to "shaft" Mr Calleary. Another TD said Mr Calleary should have told Martin to "f**k off and caused a mutiny".
Mr Calleary has not spoken publicly about the appointment but has told colleagues he objected to the position when it was offered to him by Mr Martin. He did not respond to calls last night.