The primary obstacle for Facebook to overcome will be regulatory and a number of supervisory bodies were quick to issue a statement on the plans to develop a global stablecoin nand digital wallet scheme.

Bank of England (BoE) governor Mark Carney was less hostile than some other regulatory heads, stating that he was keeping an open mind but not an open door and would subject any venture to "the highest standards of regulation".

"Anything that works in this world will become instantly systemic and will have to be subject to the highest standards of regulation."

Carney added that the BoE will look at the Libra project "very closely and in a coordinated fashion" with other regulatory bodies such as the G7, the International Monetary Fund, the Bank for International Settlements and the Financial Stability Board.

But whereas the regulatory executives were circumspect in their comments, international politicians were more forthright in putting forward their opinions.

With France due to take charge of the G7 later this year, it was French finance minister who voiced the strongest opposition to Facebook's ambitions. Bruno Le Maire told a French radio station that it was "out of the question" that Libra should become a global currency. "It cannot and must not happen," he said. 

German member of the European Parliament Markus Ferber warned that Facebook could become a "shadow bank" under its virtual currency plans. Regulators around the world have made great efforts in recent years to bring more transparency to the global banking system and to reduce the so-called 'shadow banking' market.

And in the US, members of the cross-party House Financial Services Committee called for Facebook to appear before Congress to explain Project Libra in more detail. The Committee's chair, democrat senator Maxine Waters said: "Given the company’s troubled past, I am requesting that Facebook agree to a moratorium on any movement forward on developing a cryptocurrency until Congress and regulators have the opportunity to examine these issues and take action." 

Facebook remained diplomatic in its reply to politicians and regulators. "We look forward to responding to policy makers' questions as this process moves forward."

It was not just the policymakers that raised the issue of legal and regulatory challenges facing Facebook and its Libra project. Thomson Reuters legal technologist Peter Colin said that "the potential exists for claims pertaining to consumer fraud and investor protection to increased tokenisation of assets, to how to classify and regulate Libra (as well as Facebook and its role), to user privacy and surveillance concerns and to the money laundering concerns consistently present with cryptocurrencies". 

The most postive reception to Facebook's announcement came, unsurpriisngly, from other firms working in the cyptocurrency and tokenised assets market. Crypto exchnage eToro's cofounder and chief executive Yoni Assia desribed the news as "a seismic moment for global finance".

He welcomed the fact that the blockchain on which Libra will be based is open source and decentralised but the biggest positive for the other crypto players is the legitimacy granted by Facebook's move. 

"We expect other tech giants to follow suit helping to realise the potential for blockchain to disrupt traditional financial services," said Assia.

Meanwhile, cryptocurrency investment firm KR1 co-founder George McDonaugh also welcomed the arrival of Facebook in the cryptocurrency market as well as the potential arrival of other big tech firms looking to displace banks. "Facebook has built a global phenomenon through reinventing what we've come to understand as a user experience. What they've done with interfaces, they're going to do with money, and in that arena, the banks don't have a chance.

 "Want a loan? Ask Zuckerberg, want a credit card? Ask Zuckerberg and everything will be at the click of a button on a platform that literally 30% of the planet's population are using. Further, Libra could crush merchant fees and potentially solve major issues with card fraud.

"If that wasn't enough, if Libra is successful in seeing widespread adoption, watch a slew of new coins come to market from the other Silicon Valley heavyweights. Money is the next frontier for the candy crushing, social networking leviathans and I for one would not want to be standing in their way," said McDonaugh.

The introduction of Instant Payments, Request to Pay and mobile payments has led to a seismic increase in the use of debit cards in Europe, but two billion cheques are still in circulation and each year, there is a 10% increase in the number of banknotes being issued.

“Cash is not only a means of payment, it is a reserve of value. A third of European bank notes are in circulation within the Eurozone, a third are in circulation in other regions, but the final third has disappeared,” Teissedre explains that some citizens continue to keep cash at home.

Teissedre adds that cash also promotes social inclusion and allows those without the means to access technology to manage their money. On the other hand, cash also permits citizens to “pay less” because there is no moral judgement involved in the use of physical currency.

“In an economy where there is high unemployment and high fiscal pressure, people use cash for tax evasion as they don’t want to pay VAT. When a major payment system fails, the only thing that remains is cash and coins. Cash is freedom in a society in which we are hesitating to give data and don’t want to be traced.

“A purely cashless society won’t work because people don’t change their habits overnight. We need all parts of the ecosystem to be convinced, like in Sweden and move together,” Teissedre says. Anna-Lena Wretman, CEO of Swish, puts forward the Swedish perspective and explores the drivers that have encouraged the Nordic country to become a near-cashless society.

Wretman asserts that while new technology and regulation has driven usage of modern payment methods, to return to the subject of tax, Sweden has tackled this problem with a cash register law, where every shop has a black box from the tax authority.

In addition to this, despite Swish being lauded as a changemaker in Sweden, she points out that the platform has only transformed peer-to-peer payments, and card remains the most efficient and preferred form of payment when making purchases.

Picking up on points made on inclusion, Henrik Bergman, director financial infrastructure at the Swedish Banking Association, believes that the significance in innovative forms of payment lies in educating all users how to use Swish, for example.

Banks are pressured into implementing new legislation to ensure that cash remains in circulation, but Bergman asks: “who is going to use it? Customers aren’t and merchants don’t want to handle it.” We need to do it together, banks alone cannot manage it.”

Charlotta Wark, vice president, head of banking Sweden at CGI continues this conversation and states that there is a danger in not following “society or population driven change. If citizens of one country have decided that one way [of payment] is easier and [banks] don’t provide the means of doing it. Guess what? Facebook will do it for you. Then you’re in a situation where you’re no longer in control.

“The tech giants would like to provide these services free of charge because they see this as increasing the benefits of their platform in general. We don’t have a choice, we have to provide the digital infrastructure citizens are asking for.”

The stark warning came from Anil Kashyap, a member of the central bank's financial policy committee, who was addressing a UK parliamentary committee. 

While banks cyber security efforts have mostly focused on preventing service outages, there has been less focus on attacks that seek to falsify records or corrupt data, he said. 

Consequently, for any hostile states looking "to do maximum damage", such an approach would more likely be effective, said Kashyap. 

He called on banks to bolster their defences against such attacks but also recognised the need for greater state-wide support for individual institutions. 

A commonly stated view from cyber security experts is the complexity involved in cyber attacks that look to cause long term damage to data via malware that can escape detection for weeks and months all the while causing corruption to data. For banks this can cause a problem in identifying which records have been corrupted and which have not. 

"You have this difficult situation where you have to restore the system, where you could be restoring a corrupt system," said Kashyap. 

The policymaker also warned that banks may not be concerned enough about the dangers of systemic risk caused by a cyber attack and are instead more worried about their individual fate or reputation. He referred to banks' use of a limited number of cloud providers as a systemic cyber risk. 

"I don't really care if bank 'x' is offline for a week, even if it's disastrous for their share price, if the services that they provide, that are critical, can be delivered in some other way," Kashyap said. "What is tricky is it could be the case that the (bank) board's incentives of what to worry about are misaligned with the general incentives."

Kashyap also said that the BoE would continue to monitor the market share of big tech firms looking to break into the financial services market, following the unveiling of Facebook's crypto currency and digital wallet plan.

His comments follow that of International Monetary Fund chief Christine Lagarde, who warned that big tech firms' moves into financial sertvices could threaten the stability of the global financial system.