In 1994 Manchester United were riding the crest of a wave following decades adrift in the doldrums. They had won the Premiership in 1993, the first time they had won the English league in 26 years. The following year, they retained the title and won the FA Cup to boot.

It was to be the start of a golden era for the club and its fans. No longer would they have to endure the brickbats of their illustrious neighbours in Liverpool, or other lesser lights of the league. No longer would the Irish contingent cross the Irish Sea in vain, hoping that this might be the year when they could return home cushioned by victory.

Bertie Ahern was one of the travelling United army. As we now know, he used to return from some of those matches cushioned by pocketfuls of sterling, through his foreign-exchange operation with his friend Tim Kilroe. But on one occasion in 1994 the return flight was even sweeter as he was weighed down with an envelope containing a serious packet of sterling for which he hadn't had to exchange anything. He had hit the jackpot with a whip-around. The only problem is, he can't remember now when exactly during that year this money fell into his lap. All he knows is that it was tied up with the football season.

"The end of the season is late April or May and the season starts in August," he said [during one of his Mahon tribunal appearances]. "I have never been able to pin whether it was the end. Some of my colleagues were with me because the same people attend with me regularly at these matches and they would dispute with each other whether it was the end of the season or the start of the season."

The only colleague who actually accompanied him on the trip in question was Senator Tony Kett, and Kett usually travelled to Manchester only towards the end of the season, so he reckons it must have been April or May. Originally Ahern claimed that the whip-around took place in September, but on consideration, he thought it better not to specify a date. In any event, it went down on one of his regular trips to see the Red Devils.

Ahern was staying at the Four Seasons hotel, owned by his friend Kilroe. On the eve of the Saturday match, he was invited to attend a private dinner with Manchester-Irish businessmen in the hotel. Naturally, Kilroe was there, as was another old friend of Ahern's, Micheál Wall. He was another west of Ireland man who had been forced to take the boat to escape idleness and poverty. He had done well for himself in Manchester, and owned a coach-hire business. While he was a man of considerable means, he wasn't in the league of the others at the gathering.

"I would consider Micheál Wall wealthy. I would consider the others extremely wealthy," Ahern said. "You are talking about serious people. Every one of these people [apart from Wall] was worth £50m plus at the time."

Wall didn't eat the dinner that night. Maybe he declined or was excluded for hierarchical reasons: he wasn't worth £50m. He said later that he drove the bus that transported some of the diners to the hotel. That might have been sufficient reason to refrain from dining if he thought the presence of wine might prompt him to imbibe and therefore render him ineligible to drive them back – the multimillionaires would have had to walk home. Or maybe he just wasn't hungry that night. Whatever the reason, Wall appears later in Ahern's financial narrative in a role that more than made up for missing out on contributing to the whip-around.

Everybody else agreed to sit down in the Four Seasons restaurant and get stuck into the nosh. Twenty to 25 people were present. By Ahern's calculation, this implies the net worth of the table was in excess of £1bn, which is as prosperous a gathering of Irishmen as you are ever likely to find.

Despite the status of those in attendance, and Kilroe's ownership of the establishment, the dinner took place in the main hotel dining room. If it had been held in a private room, there is at least a slight possibility that a written record would have been kept. Sadly, none was.

Ahern knew many of those present. He had been to several such informal functions on his regular jaunts to Manchester.

"I would have known a number of them very well," he said. However, when asked 12 years later to identify those present, he was at a loss. "I have tried to track back everybody who was in that room that night, but it is difficult," he said.

We do know that Tony Kett was present. He gave sworn evidence to that effect, as did one of the multimillionaires, John Kennedy.

"I recall personally donating a sum of £1,000 to Bertie Ahern for his efforts in changing the face of Irish politics," Kennedy said, years later. He had thrown his cash into the metaphorical hat that was passed around.

Apart from Kennedy and Kett, Tim Kilroe was the pivotal figure in the gathering, but he died before the whip-around came to public attention. That leaves 17 or 18 Irish multimillionaires living in Manchester who can't be identified for love or money.

Ahern remembers some detail of the dinner: "It was a meal with a group, a hot group, all Irish people, most of them in Manchester for a considerable time, who I have met many times before and since, and it was a meal that, where [it was] informal but still [had] a question-and-answer session, talking about the Irish economy, talking about the country. I would have attended an enormous amount of events in Manchester, officially and unofficially, over the years."

The talk of the economy and the Q-and-A session to which he refers occurred once the eating was done. Ahern stood up in the dining room and gave the businessmen his perspective on the economy back home. He was not speaking in his official capacity as Minister for Finance but as a private citizen, whose insights these boys were eager to digest.

The nature of the address is unclear. Tony Kett recalls it like this: "I would consider it a talk more than a speech. He didn't read from notes. He spoke for 20 minutes to half an hour and thereafter had a question-and-answer session."

When it ended, the gathering repaired to the hotel bar where they remained for some time. Naturally, many of the multimillionaires engaged personally with Ahern, thanking him for his time. Tony Kett also orbited the group, as a sort of appendage to the main attraction.

"He was the man of the moment, so to speak," Kett said. "He was the one they wanted to listen to and hear. He asked me to tag along."

At some stage, Kilroe slipped up beside Ahern. "I remember Tim Kilroe approached me with, I think, one or two of the others and said they appreciated me coming over, appreciated me being there," Ahern said. "I had done questions and answers and talking to them, just general talk, and he said he wanted to make a contribution. He made a contribution and I recall that."

The businessman passed an envelope to the finance minister. Ahern was surprised. He hadn't expected this.

"Before, they gave me books and glass and things like that," he said."On that occasion, that's why I remember it, it was the only time they gave me a financial contribution."

Ahern hesitated. He wanted to be sure the money was for performing a function with his Joe Citizen hat on, rather than any ministerial garb.

"The only question I did ask him, I asked was it a political contribution as I would have to give it to the party. He said it was a personal contribution for me coming over. It was nothing to do with the party."

Relieved that he could tell himself he was breaking no codes or laws, Ahern thanked his host and slipped the envelope into his pocket. Understandably, he didn't count the money there and then. To do so would have been rude to his host and the other multimillionaires.

The following day, he was at Old Trafford. He hadn't counted the money in the envelope before he went to the match. He didn't count it after the match. It is unclear whether he left the stuffed envelope in his hotel room or whether he was happy to walk around with it for the day. As he can't remember whether it was in May or September, there is no knowing who the opposition was and whether United won the match.

Either that Saturday evening, or the following day, he flew back to Dublin. It must have been a satisfying flight. Whatever the result – and we can hazard a guess that Manchester United won on the basis of the team's outstanding form that year – the trip had been a success. While Ahern was accustomed to flying home with large amounts of sterling following encounters with Kilroe, this was different. It was free, the proceeds of a whip-around rather than an exchange of currency. Yet, despite his good fortune, he hadn't yet counted the money.

During the flight, he told Kett what had happened. Until then, Kett had been blissfully unaware of his friend's good fortune at the Four Seasons bar. "He sounded surprised," Kett remembered.

Some time on the Monday, in his office in St Luke's or upstairs, Ahern pulled out the envelope and finally counted out the £50 notes. The total amounted to around £8,000 in cash. The men who had been present had coughed up an average of £400 each for their evening's entertainment. They must all have been accustomed to carrying large wads of cash, as the whip-around was spontaneous.

Even though he had rejoined the world of banking at the start of that year, Ahern reverted to type and put the cash into his safe. If he had lodged the money in a bank, a foreign-exchange slip would have recorded the transaction. However, he seemed to retain a sliver of suspicion about banks. He didn't think much about it one way or the other.

"It was £8,000," he said. "Let's be frank about it. It was no big deal. It was no big deal."

And so it wasn't, for at that time he had money coming out of his ears. Between cash and his savings account, he had around £70,000, and his building-society account was in credit to the tune of £19,000. He certainly had no money worries. Except, perhaps, that people wouldn't stop handing him cash out of the blue.

Yet, despite his prosperity, others around him remained under the impression that he was short a few bob, that he couldn't even afford the price of a deposit on a house. After all, wasn't he living upstairs in St Luke's which, for all its strengths as a base, was hardly suitable for the man who would be taoiseach? It was time for another batch of friends to step up to the plate.

Book Details

Extracted from 'Bertie Ahern and the Drumcondra Mafia' by Michael Clifford and Shane Coleman, which is published on Thursday by Hachette Ireland at €14.99