Todd Thomson, the Citigroup executive who resigned amid claims of largesse on corporate aircraft involving Maria Bartiromo, the CNBC presenter known as the “Money Honey”, has turned on his critics for the first time.

The former head of Citigroup’s wealth management group left in January, supposedly to pursue other interests.

However, it was widely understood that Mr Thomson was forced to leave over his extravagant use of company funds at a time when Citigroup was under pressure to cut costs.

He declined to comment at the time but he has now accused Charles Prince — the chief executive of Citigroup who was ousted this week over disastrous figures at the bank in the wake of the credit crunch — of orchestrating a smear campaign against him.

“I was the only business that had expense growth less than revenue growth. I was Sandy’s [Weill] CFO for four and a half years. You think I somehow lost my cost-management capabilities? This is insane.”

Mr Thomson was hired from General Electric in 1998 by Mr Weill, the founder and then chief executive of Citigroup, who was known for relentless cost-cutting.

Mr Thomson was promoted to chief financial officer in 2000 and in 2004 he swapped jobs with Sallie Krawcheck, who was the head of wealth management.

During his tenure Mr Thomson had developed a reputation as a free-spender and his sprawling office overlooking Central Park in New York was known as the “Todd Mahal”.

Mr Thomson said the office space in Midtown Manhattan saved Citigroup money because it cost only $44 a square foot compared with about $80 a square foot at the bank’s larger headquarters on Park Avenue.

However, an incident in November is thought to have caused Citigroup to lose its patience.

It is understood that Mr Thomson flew a group of employees to China but left them there to make their own flight arrangements home, at considerable extra expense to the bank.

Mr Thomson, meanwhile, returned on the corporate jet, accompanied by Ms Bartiromo.

At the time CNBC confirmed that Ms Bartiromo had taken the flight but said that she had sought and received permission from the channel, which had paid the fare.

Mr Thomson, who is now chief executive of Headwaters Capital, an investment company, said he suspected that Mr Prince was one of the people who fed stories to the media as a way of deflecting criticism about Citigroup’s costs.

Mr Thomson said: “There was a very significant rift between me and the now ex-CEO. To be clear, there was nothing I did at the company that was in any way untoward.”

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