"I was approached by the man who was mentioned in Wikileaks, Jonathan Moyo, and listened," he said. "Eventually, we decided not to do anything with him. We just weren't completely sure that his was the best approach.
"We have subsequently done some things for and in Zimbabwe, on some of the issues that were discussed at those meetings, but we ultimately felt that working with him wasn't necessarily the right way forward."
But it is Branson's description of his dealings with Gono, far more influential than Moyo and one of Mugabe's inner circle, that will most raise eyebrows in Harare.
Branson says he talked to him about the possibilities of regime change.
According to Branson, the scheme came into being because he had a chance meeting with Gono at an airport in South Africa early in 2007.
At the time, Zimbabwe was suffering from rising volatility before elections the following year.
They had a short discussion at which several ideas for Mugabe's removal were raised. Those ideas were later fleshed out in emails, then elaborated on in several days of face-to-face meetings which Moyo, but not Gono, attended in Johannesburg in July that year.
That account contradicts an earlier version from Moyo, who told the Zimbabwean Daily News that he was the conduit between Branson and Gono, who refused to pass the message on to Mugabe.
Gono refused to comment on those claims and could not be reached for further comment.
"I remember meeting Gideon Gono at an airport," Branson said. "I can't remember whether I also met Moyo then. Maybe they were together ... We did later meet [Moyo] and we did put him up in Johannesburg for a few days, but we decided not to continue with him."
Gono is a controversial figure in Zimbabwe, since his time as the nation's top banker has coincided with hyper-inflation that has exacerbated the nation's economic ruin.
His private life also makes headlines - last year, he was forced briefly into hiding amid rumours that he had a five-year affair with Mugabe's wife, Grace.
Under the plan Gono and Moyo helped hatch, Mugabe was to have been approached by Nelson Mandela and a collection of other respected figures from the region.
They would have tactfully claimed they wished to protect his legacy, and safeguard Zimbabwe's future by organising a peaceful transition of power.
Mugabe was to be offered immunity from prosecution, as well as the chance to appoint an interim prime minister.
In return, he would co-operate with a truth and reconciliation process modelled on South Africa.
The existence of the scheme was made public this week, when Wikileaks published classified cables written by the United States ambassador to Pretoria, Eric Bost.
He had obtained copies of several emails between Branson and Moyo, and was eager to outline their plan to his superiors in Washington.
The Daily News, which broke the Wikileaks story on Monday, claimed that Branson had been prepared to "offer Mugabe a £6.5 million incentive to stand down" as part of the plan. That element of the story is untrue, Branson insists.
"It was never discussed. It would have been cheap at the price, but it just happens not to be true."
Branson said he was troubled by the revelation that a US diplomat had apparently been able to get hold of sensitive private emails.
"Obviously, they must be listening in, or doing something," he said. "I have no idea how they got them. I've no idea how it happened."
His recollection of the affair raises questions about the public statements Moyo has made this week.
On Wednesday, for example, Moyo told the Independent that his only meeting with Branson had been in a check-in queue at Johannesburg airport in April 2007.
"We chatted for about an hour and a half," Moyo said. "When he learned I was an MP, he was interested in my views. Mr Branson is a good man."
Although the 2007 scheme came to naught, Branson said that the "elders" - a group of world leaders he subsequently helped form - played a central role in setting up Zimbabwe's coalition government after the 2008 elections.
He said his interest in easing Mugabe from office was in no way motivated by a desire to expand any of his Virgin ventures into Zimbabwe.
"It was nothing to do with my businesses," he said. "Most of my time now, about 70 per cent, is spent on philanthropic work. And if I'm in a position to help with resolving conflicts, I believe I should do so."
Branson was speaking at the Reagan Library just outside Los Angeles, where he appeared on Thursday at a summit of Global Zero, an international organisation of political, military, business, civic and faith leaders who are campaigning for nuclear disbarment.
- INDEPENDENT
