Lord Ballyedmond, a peer in the House of Lords who is believed to be one of the richest men in Northern Ireland, was among those who died in a helicopter crash in Norfolk on Thursday.
The peer, also known as Dr Edward Haughey, 70, was chairman of Norbrook, the largest privately-owned pharmaceutical company in the world.
He was killed along with three other people - two pilots and a man from Mayobridge in County Down - when a helicopter came down in thick fog in a field in Gillingham in Norfolk, near Beccles, at 7.30pm on Thursday.
Lord Ballyedmond owned Gillingham Hall, a stately home near the crash site. A life peer with a seat in the House of Lords, first on behalf of the UUP before switching to the Conservative Party, his wealth was estimated to be over £400m, perhaps £600m.
First Minister, Peter Robinson said: “Dr Edward Haughey was a great ambassador for Northern Ireland. He worked tirelessly to develop the globally respected Newry based veterinary pharmaceutical company Norbrook Laboratories. As a result of his vision and leadership he created employment opportunities for many people in Northern Ireland.”
His death will be “a great loss to his family and everyone in Northern Ireland” he added.
Deputy First Minister Martin McGuinness added: “Eddie was a highly motivated man with immense business skills and my thoughts and prayers are with his family at this most difficult time.”
The US government also paid tribute, saying he had played “a profoundly significant role in politics and commerce across the island of Ireland, Great Britain, and beyond” while adding that his company, Norbrook became “a global force in veterinary pharmaceutical research and manufacturing”.
Secretary of State Theresa Villiers said the peer created many jobs and opportunities “as well as serving with distinction in the Irish Senate and later in the House of Lords”.
UUP Peer Lord Empey has known the Haughey family for 25 years. “This tragic accident has cut short the life of a man who had still much to give,” he said.
Fianna Fáil leader Micheál Martin said the tycoon’s work in the lead up to the Good Friday agreement, “mark him out as an important figure in the progress of peace and prosperity on the island of Ireland”. Likewise Tánaiste and Irish Minister for Foreign Affairs Eamon Gilmore described him as “a visionary businessman” whose interests and influence “spanned both sides of the border”.