Mutual fund Fidelity is denying claims that bitcoin can be used in self-directed IRAs (Individual Retirement Accounts) held through the company.

On Wednesday, CNBC and MarketWatch both reported that Fidelity's investors could choose to invest funds in the Bitcoin Investment Trust (BIT). However, Fidelity was quick to deny the reports.

Bitcoins for retirement - if you're a Fidelity client you can invest your self directed IRA in the Bitcoin Investment Trust. $25k minimum.

— Mary Thompson (@MThompsonCNBC) December 11, 2013

Fidelity responded via twitter that it was not offering bitcoin investment through its platform.

Claims in @MarketWatch’s article are inaccurate. Bitcoin investing is not currently available through our retail platform, including IRAs.

— Fidelity Investments (@Fidelity) December 12, 2013

BIT was launched in September by SecondMarket, who teamed up with several other self-directed IRA providers to allow investors a straightforward way to make IRA investments in bitcoin. BIT claims to currently have net assets of $58.8m.

Barry Silbert, CEO at SecondMarket, said: "The Bitcoin Investment Trust was previously approved by Fidelity as an eligible investment for accredited clients in their self-directed IRA accounts and investments began closing last week. We understand that Fidelity has decided to reevaluate this decision."

He went on to say BIT remains an approved investment on the PENSCO, Entrust, Millennium and Equity Institutional self-directed IRA platforms for accredited investors.

"We expect to add other platforms to the approved list shortly. Eligible investors can also invest directly through the BIT website," Silbert concluded.

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