BERLIN – Finance ministers from five of Europe's biggest economies called Friday for the European Union to produce strict rules for new, private digital currencies such as Facebook-backed Libra and ban those that don't comply.The ministers from Germany, France, Italy, Spain and the Netherlands said in a joint statement that new regulations being drawn up by the EU's executive Commission — and expected this fall — should seek to “preserve our monetary sovereignty and address the risks to monetary policy, and on the other hand protect EU consumers.”The five countries say that if it isn't clear that a digital currency is firmly linked to an existing currency, and if there is a danger to the stability of financial markets, “what has got off the.