Joan Burton's gloves are off over welfare 'reform' plans
Only proposal is no proposal, minister will say
In a politically charged interview with the Sunday Independent, Ms Burton launched a scathing attack on a number of her Fine Gael cabinet colleagues.
And she refused to rule herself out of a future leadership contest, as one senior Labour source told the Sunday Independent that Eamon Gilmore had just "21 days to save his leadership".
Ms Burton firmly ruled out any further bailout for James Reilly's Health Department, which is already believed to be €250m over budget this year.
On two previous occasions, savings from the Department of Social Protection have been transferred to Dr Reilly's department.
But Ms Burton said this weekend: "I am no longer prepared to see savings I have made in Social Protection going into a black-hole in the Department of Health. I want that money well-spent."
The Labour deputy leader said the economic recovery meant there could be "no more social welfare cuts and no more education cuts".
Despite improving economic figures, the Government still has to find an anticipated €2bn in cuts and taxes in Budget 2015.
Separately, the Sunday Independent has also learnt that tensions are high between Ms Burton and Taoiseach Enda Kenny over the politically thorny issue of child benefit.
Last week, Mr Kenny publicly said at a meeting attended by Ms Burton that he expected her department to bring in proposals to reform child benefit.
But a senior Labour source told the Sunday Independent: "Joan will tell the Taoiseach the only proposal she has is that there are no proposals."
The source added: "Kenny's fiscally hawkish elements want us to cut benefit for the middle and the lower tier, Kenny himself has pointedly mentioned it. But we will not be cutting child benefit, tensions are high."
Ms Burton was also deeply critical of Fine Gael's failure to address Labour's concerns over water charges.
She told the Sunday Independent: "The Irish Water issue and how Fine Gael dealt with it was shocking.
"We said we didn't want a gold-plated Irish Water, we wanted a rational system that would protect the vulnerable put in place."
In what will be seen as a criticism of Environment Minister Phil Hogan, Ms Burton added: "The revelation about metering, that notion that you could price up without metering, was astonishing both for senior and junior Labour ministers."
Ms Burton's public criticism of Fine Gael is likely to accelerate growing tensions between the increasingly fractured Coalition.
But her call for her own party to take a far more assertive role in government once the local and European elections are over will be even more closely analysed by what one source described as "a deeply paranoid Labour leadership''.
No other Labour figures have turned on Mr Gilmore in the wake of the recent attack by Ireland South candidate Phil Prendergast on the "chronic inability" and inert nature of his leadership.
Commenting on Ms Prendergast's outburst, Ms Burton said: "It was not helpful at that point in time. I rather wish she had found time to talk with other members of the Labour Party."
But she warned: "The electorate will send a message on May 23, we would not be in the business of politics if we did not listen to it."
And while Ms Burton declared her ongoing confidence in Mr Gilmore, she pointedly did not rule herself out of any future leadership contest.
She said: "In the Labour parliamentary party I would have thought every single person has ambitions, myself included, to serve the party at the highest level."
Meanwhile, support within Labour for Mr Gilmore appears to be drifting away.
One Labour TD told the Sunday Independent: "We are already in the post Gilmore age.''
Another TD said: "Do you not see the body language, the old guard are preparing to anoint Alex White, [Pat] Rabbitte knows the jig is up, [Sean] Sherlock will represent the Workers Party, Alan Kelly will be in the field and then there is Joan."