The Taoiseach has been accused of disrespecting nurses and patients by issuing "cynical" press releases instead of directly engaging with unions.
As nurses across the country engage in a second 24-hour strike, Leo Varadkar has come under sustained questioning and criticism in the Dáil over the Government's handling of the dispute.
Calling on Mr Varadkar to replace "substance with spin" Fianna Fáil leader Micheál Martin slammed the "pathetic" approach taken and the absence of "substantive and meaningful engagement" on the Government side.
He pointed to a press release issued by Health Minister Simon Harris and Finance Minister Paschal Donohoe on Monday night which said the Government would be willing to engage in talks on conditions but failed to mention pay increases.
"You cannot resolve industrial disputes by such cynical PR manoeuvres, that kind of 'optics are more important that substance' approach won't cut it when it comes to an industrial dispute of this gravity and scale," said Mr Martin.
He said the statement "only served to compound the problem and make it worse".
Responding, Mr Varadkar said the statement was a "sincere offer".
"I appreciate that the nurses union felt that the offer to engage in further talks at the WRC was discourteous as they heard it through a press release and not a letter or direct contact and we will make sure that that does not recur," the Taoiseach told the Dáil.
But in thinly veiled attack on the nursing unions he added: "We shouldn't forget that tens of thousands of people found out through the media that their respite was being cancelled this week too and that their daycare was being cancelled too."
Mr Martin dubbed the Taoiseach's explanation "pathetic".
"Have you reprimanded your ministers? What were they at last night?" he asked.
"It's appalling that a Taoiseach would come in here today and say that we engaged in optics last night essentially, we didn't make any direct contact in terms of the offer that was announced.
"It's a pathetic way to approach such a a grave, grave dispute," Mr Martin said.
Sinn Féin president Mary-Lou McDonald called for "engagement with no preconditions".
But Mr Varadkar said the dispute would have to be resolved "under certain parameters".
He said any deal would have to affordable to the taxpayer and fair to all other public servants.