The Greek stock market closed hours ago, but the exchange-traded fund that tracks Greek stocks crashed during the final minutes of trading in the US markets. This comes following bad news from the European Central Bank (ECB) to Greece. Shortly after 3:30 p.m. ET, the ECB announced that it lifted its waiver on minimum credit rating requirements for marketable instruments issued or guaranteed by Greece. To put it another way, Greece can't exchange its poorly rated bonds for money. "The waiver allowed these instruments to be used in Eurosystem monetary policy operations despite the fact that they did not fulfil minimum credit rating requirements," the ECB said in a press release. "The Governing Council decision is based on the fact that it is currently not possible to assume a successful conclusion of the programme review and is in line with existing Eurosystem rules." "In other words, the ECB doesn't see Greece complying with existing bailout rules," Bloomberg's Lorcan Roche Kelly explained. However, it's not all bad. The ECB has another way for Greece to exchange its securities for liquidity. "Liquidity needs of Eurosystem counterparties, for counterparties that do not have sufficient alternative collateral, can be satisfied by the relevant national central bank, by means of emergency liquidity assistance (ELA) within the existing Eurosystem rules," the ECB said. "The move from the ECB today is a copy of the suspension of Greek debt that occurred in February 2012," Kelly noted. More to come...Join the conversation about this story » NOW WATCH: Nationwide's Super Bowl commercial about dead children is about corporate profits ... in a way that we can all appreciate