The Fine Gael leader, Mr Enda Kenny, has characterised the Government as "disgusting", riven by dissent and economically, socially and morally bankrupt.
In a speech designed to motivate party members before next year's local and European elections, Mr Kenny called on voters to "vote Fine Gael to send a stark message to this disgusting Government. Three words: out, out, out."
He told a party conference in Cork on local government that his party would fight a vigorous election campaign, fielding high-calibre candidates in every ward and electoral area.
"We must hammer home the message that these elections are the first step in replacing Fianna Fáil and the PDs. Economically, socially and morally, they are bankrupt. Their failure to lead has become pathological."
Quoting Britain's Jack Straw, he accused Fianna Fáil and the PDs of "making a complete horlicks" of running the country. "This Government has lost control. It is now driven by internal dissent, failure to adhere to collective cabinet responsibility. We see daily examples of ministerial insubordination. The Taoiseach's position has been seriously undermined and the people clearly feel that there is now no one in charge.
"It's time for honest government. Government that leads, not follows. Government that will live up to its patriotic and moral duty to put the good of the country over the popularity of the party. Government led by Fine Gael."
His party had "a moral duty" to provide and lead an honourable alternative to "this dangerous administration . . . The public has been badly burnt by the junk politics of this Government.
"Next time, they'll want the real thing. And we must provide it. That's our challenge, that's our goal."