Sinn Féin and the Democratic Unionists are no longer close to a deal to restore powersharing in the North, Taoiseach Leo Varadkar has said.
Mr Varadkar said hopes of an imminent agreement had emerged last week but those had now receded.
In a forthright assessment of the impasse, the Fine Gael leader said "big things" were not being dealt with in the North because the two main parties were "arguing about the intricacies of an Irish Language Act".
On the apparent backwards direction of the talks, he said: "I will let the different parties account for themselves as to what went wrong."
Mr Varadkar was asked about the state of the long-running negotiations to salvage Stormont's devolved government during a visit to storm hit areas in Co Kildare.
"At the moment they are not close to a deal," he said.
"Things did look encouraging at the start of last week and became less favourable during the week."
Stormont imploded at the start of the year over a row about a botched green energy scheme.
That wrangle exposed more deep-seated issues dividing the DUP and Sinn Féin.
Months of negotiations to restore devolution have stalled, with disagreement over proposed legislation to protect Irish language speakers currently the main sticking point in the way of a deal.
Mr Varadkar listed the pressing problems the North faced in the absence of a functioning government.
"There are big things to deal with," he said.
"Brexit could have a huge impact on Northern Ireland, their public services are about to run out of money because the budget allocation is running out, they have big challenges in their health service, just as we do, and, as you know, they are facing some very severe water damage and, meanwhile, both the DUP and Sinn Féin are arguing about the intricacies of an Irish Language Act.
"It would seem to me that what the people of Northern Ireland want is for their politicians to get together and start looking after the business of Northern Ireland and making sure that Northern Ireland has a unique voice in these negotiations on Brexit."