The UK brokerage platform of Citibank, Citigroup's (C) consumer division, is now offering clients access to Ether exchange traded notes (ETNs), according to XBT Group, a Sweden-based company that is providing the cryptocurrency investing platform.

Ethereum is the second most popular cryptocurrency with investors after Bitcoin. What distinguishes Ethereum from Bitcoin is the technology behind Ether, the unit of cryptocurrency used on the Ethereum blockchain.

Today Ethereum is trading at $295 and has a market cap if $28 billion.

XBT Provider, a CoinShares Company is the group behind the first Bitcoin and Ether ETNS. Last month, the group listed the world's first two Ether-tracking ETNs on Nasdaq Stockholm.

Citibank move to give consumers access to Ether is yet again another positive move and for the cryptocurrency market.

Earlier this week, the Chicago Mercantile Exchange (CME) Group announced it will launch Bitcoin futures this year. That legitimized the cryptocurrency all the more and send its valuation skyrocketing above $7,000.

"I am particularly excited for UK investors who can now gain access to the exchange traded ether note via Citibank UK's brokerage platform," said Laurent Kssis, managing director of XBT Provider by CoinShares. "We've been working diligently to ensure that qualified UK investors have access to the ether ETNs, via their brokerage of choice, and the addition of access via Citibank UK is an important piece of this mission."

"The addition of the ether ETN to the Citibank UK platform is yet another indicator of the rapid maturation of the crypto-asset space," Kssis added. "At CoinShares our focus is satisfying market demand by delivering the most fit for purpose, professional investment vehicles possible; a mission validated thus far by the response to the ether product from investors - more than $20 million in AUM in less than three weeks - and institutions such as CitiBank UK."

At press time, Citibank failed to provide a comment on Ether ETNs.

It is no secret banks and traditional financial institutions have been resistant to acknowledging cryptocurrencies. The most vocal on this investment type has been JPMorgan (JPM) CEO Jamie Dimon who criticized Bitcoin and dubbed it a "fraud' and "worse than tulip bulbs."

There are a number of banks taking a look at crypto, some with a more positive outlook. For example Goldman Sachs (GS) CEO Lloyd Blankfein's has also in the past acknowledged Bitcoin and expressed the possibility that Goldman could get involved in the cryptocurrency, potentially via a trading operation focused on Bitcoin.

UK investors can also access Ether and Bitcoin ETNs through a capital markets company called Hargreaves Lansdowne. The Bitcoin and Ether ETNs can be placed in a self-invested personal pension (SIPP). The move from Citibank further confirms the continued momentum for the mainstream adoption of crypto-currency by financial institutions.

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