The Irish government maintained a close working relationship with Senator John McCain, and two of its top representatives issued statements paying tribute to the late senator.

“It was with great sadness that I learned of the passing of Senator John McCain, who was one of the outstanding political figures of his generation. I would like to extend my deepest condolences to his family and many friends. Senator McCain cherished his Scots-Irish heritage. He was a great friend of Ireland, including on immigration issues,” Irish Ambassador to the U.S. Dan Mulhall said.

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“He leaves behind a remarkable legacy of statesmanlike political activity. His devotion to his country and to public service was of the highest order. His steadying influence will be missed. Ar dheis Dé go raibh a anam.”

Irish President Michael D. Higgins said, "Members of the Irish communities in the United States of America will have heard with sadness of the death of Senator John McCain of Arizona, after a brave battle with cancer.

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"They will recall his efforts with the late Senator Edward (Ted) Kennedy and others to achieve a resolution of the position of out-of-status immigrants, including the Irish, in the United States.

"His commitment to bi-partisanship on a number of issues should also be acknowledged and particularly his efforts, for example, to attend crucial votes in the United States Senate at some of the most difficult periods of his illness.”

Taoiseach Leo Varadkar said on Twitter, “On behalf of the people of Ireland, I extend my deepest sympathies on the death of Senator John McCain, a wise and remarkable statesman, U.S. ally of Ireland and a proud Scots Irishman who was a champion for immigration reform in the U.S. Senate.”

On behalf of the people of Ireland, I extend my deepest sympathies on the death of Senator John McCain, a wise and remarkable statesman, US ally of Ireland and a proud Scots Irishman who was a champion for immigration reform in the US Senate.

— Leo Varadkar (@campaignforleo) August 26, 2018

Senator John McCain.Gage Skidmore