The DUP's new leadership team has faced criticism on both sides of the border after Taoiseach Enda Kenny was accused of being "disrespectful" in remarks about the consequences of Brexit.
During a visit to London on Monday where he met British Prime Minister David Cameron, the Fine Gael leader warned that a UK exit from the European Union – known as 'Brexit' – would create "serious difficulties" for Northern Ireland.
In common with most of the Republic's parties, the taoiseach is stridently pro-European and believes Britain should remain part of the EU after it has secured reforms Mr Cameron is seeking.
"Europe will be much stronger with Britain as a central and fundamental member," he said.
"So it is a vital issue for Europe, it is a vital issue for Britain but it is also a critical issue for Ireland."
Mr Kenny added that Brexit would have an adverse effect north of the border.
Analysis: Enda Kenny voicing legitimate Brexit concerns
But his remarks were labelled "disrespectful" by DUP deputy leader Nigel Dodds, who said it was "counterproductive" for the taoiseach to "lecture us as to what is best for Northern Ireland".
"I trust that Enda Kenny will keep this in mind when making future comments about the EU referendum," the North Belfast MP said.
The Fine Gael leader's intervention also drew criticism from First Minister Arlene Foster, who said that while Mr Kenny had a right to express an opinion on Britain's relationship with Europe, the decision on whether or not to remain within the EU was down to its electorate alone in a referendum planned this year.
"It is for the people of the UK to decide what's the best way forward and, as you know, we don't take too kindly to people telling us what to do," she said.
Fianna Fáil border region spokesman Brendan Smith described Nigel Dodds's comments were a "regrettable throwback to a time of cross-border insults and groundless suspicion".
"Whether Nigel Dodds likes it or not, the issue of Brexit is one that involves and affects all the people of this island," the Cavan–Monaghan TD said.
SDLP leader Colum Eastwood also agreed with Mr Kenny's assessment of the consequences of Brexit on the north.
He claimed the DUP deputy leader's remarks "reflect a mindset which reminds us of a time past", adding that as a co-guarantor of the Good Friday Agreement, the taoiseach had every right to speak out.
"The Irish and British governments share a good and constructive relationship, with trade between the UK and Ireland worth £1bn a week and trade between Northern Ireland and the Republic is at least £1.6bn annually," Mr Eastwood said.
