The billionaire is said to be no longer on speaking terms with McCann, who worked for many years as his "fixer". Friends of McManus say he has cut off contact with McCann after a dispute over the booking of a private box at Ascot last month.

When contacted by the Sunday Tribune, the Limerick native said: "I have no comment to make, none at all. Very good."

Terry McCann, who is in his early 60s, also declined to comment on the story, saying he was in hospital.

It is believed McCann was central to the planning of McManus's daughter's lavish wedding which takes place this week.

However, since the row, McCann is no longer involved in organising the massive marriage of Sue Ann McManus and Cian Foley, which takes place in Martinstown, near Kilmallock this Saturday.

McCann was a good friend and trusted confidant of the businessman; he booked tickets, flights and took care of any other requests that McManus had. If Tiger Woods was coming to Ireland, McCann would ensure that every plan was in place to ensure that his visit ran smoothly.

A source said: "The lads had a falling out over the booking of a private box at Ascot and Terry is no longer working for JP and that is the way things will remain. They were very close for years and Terry would always have been at his side and is a familiar face around Limerick. He was organising the wine for the wedding and everything."

Over 1,000 people will descend on Limerick for the wedding celebrations.

McManus has laid on a fleet of limousines and helicopters to ferry the guests to the wedding mass at the newly refurbished Martinstown parish church.

The congregation will then descend on the McManus family estate near Kilmallock. The reception will take place in the 100 million, 40,000 square-foot home which is 27 times the size of an average house.

McManus, who is a gambling expert, has told friends no expense will be spared to ensure his only daughter's big day goes perfectly.

He has bought the bride a 4.5m country estate as a wedding gift.