A MILLIONAIRE currency trader from Hampshire could be jailed for at least seven years after defrauding an energy company in a £2.7bn currency deal.

Last year former HSBC executive Mark Johnson was convicted of nine charges of fraud and conspiracy following a month-long trial in New York.

The 51-year-old father of six was found to have manipulated currency values, making £5.5 million for HSBC at the expense of its client.

The US Department of Justice (DoJ) claims Johnson should be jailed for at least seven years and fined between $30,000 (£21,126) and $300,000 (£211,341) to deter other traders from misusing client information.

In its sentencing memorandum the DoJ says only a substantial fine and a prison sentence of no less than 84 months will be sufficient.

It is not known when the sentencing will take place.

Johnson, who owns a £1.8 million mansion in Burley, is a keen rugby player who formerly captained a side at Ellingham and Ringwood Rugby Club.

In 2011 Edinburgh-based Cairn Energy asked HSBC to convert proceeds from the sale of an Indian subsidiary from dollars into pounds.

But Johnson took part in a practice known as "front running", which involves ramping up the price of sterling in advance of an exchange.

During the trial it was alleged that Johnson and another HSBC executive bought sterling ahead of the deal, inflating the currency's value and thus forcing Cairn to pay a higher price.

US prosecutors played tape recordings of phone calls, including one in which Mr Johnson said: "I think we got away with it."

He also discussed how high the pound might go before Cairn would "squeal".

Kenneth Blanco, of the DoJ, said: "The defendant manipulated the foreign exchange market for the benefit of the bank and his bonus pool, to the detriment of the bank's client."

But Johnson said buying sterling before a Cairn-type deal was an accepted practice known as pre-hedging and claimed the company got a fair price.

Speaking after the trial his attorney, John "Rusty" Wing, said: "They've convicted an innocent man."

HSBC has not been accused of any wrongdoing in the case but is involved in settlement talks with the Justice Department and US regulators.

Johnson, the first financier to be tried in the US on currency rigging charges, left the bank earlier last year.

Speaking at the time, one of Johnson's neighbours spoke of her shock at his arrest, describing him as a "lovely man" whose detention had come as a "total surprise".

HSBC has declined on comment on Johnson's conduct and conviction.