NEW YORK (TheStreet) -- Shares of National Bank of Greece  (NBG) are down 6.95% to $1.40 in afternoon trading today as Greek markets declined.

The Global X FTSE Greece 20 ETF (GREK), designed to reflect broad based equity market performance in Greece, was down 5.21% to $11.73.

The Greek markets reacted today as Greece repaid the first 310 million euro installment of a loan from the International Monetary Fund that falls due this month, as it scrambles to cover its funding needs, Reuters reports.

The country's government must pay a total of 1.5 billion euros to the IMF this month, with the following payments due in installments on March 13, 16 and 20.

Greece's central bank chief Yannis Stournaras said today that Greek banks were "sufficiently capitalized and faced no problem with deposit outflows," according to Reuters.

"There is full support for Greek banks [from the ECB], there is absolutely no danger," Stournaras said, but added that Monday's upcoming meeting of euro zone finance ministers has to be "successful."

Insight from TheStreet's Research Team:

Separately, those who were still hoping for a swift resolution of the issue of the Greek debt at the heart of the eurozone were left disappointed by the European Central Bank's news conference yesterday, TheStreet's Realmoney.com contributor Antonia Oprita said.

Oprita thinks that Greece will keep "roiling" the markets. Here's a snippet of what she had to say:

While ECB President Mario Draghi duly announced the beginning of sovereign bond purchases next Monday, he confirmed that Greek bonds are excluded. (You can find more details about how bond purchases will work on the ECB's website; one key issue is that they put a floor on negative yields: the central bank won't buy government bonds whose yields are more negative than its own deposit facility rate -- that's currently at minus 0.2%). And there were other ominous signs for Greece's already fraught relationship with the eurozone in Draghi's conference.

Greece's left-wing Syriza government is at loggerheads with the other eurozone member states over its bailout program. The government is insisting that it does not want an extension of the austerity that was a condition of the program, while the Troika -- made up of the International Monetary Fund (IMF), the European Union and the ECB -- says the conditions of the bailout must be fulfilled for Greece's economy to be able to recover. Furious Greeks have accused the ECB of helping all other eurozone countries but theirs -- there was a bit of shouting in Greek during the ECB's conference, which this time was held in Cyprus -- but Draghi denies this.

He stressed the fact that the ECB has doubled its total lending to Greece, to 100 billion euros ($110 billion) just in the past two months. That represents 68% of Greek GDP and the highest level of ECB lending in the whole of the eurozone. "The last thing that anyone can say is that the ECB is not supporting Greece," he said.

Today's clarification from Draghi on the bank's position regarding Greece's debt is more of a political than a technical statement: it signals the unwillingness of at least one member of the Troika to make any more compromises. Investors should expect more volatility ahead for the eurozone, despite the ECB's quantitative easing.

-Antonia Oprita, 'Greece Will Keep Roiling the Markets' originally published 3/5/2015 on Realmoney.com.

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Separately, TheStreet Ratings team rates NATIONAL BANK OF GREECE as a Sell with a ratings score of D. TheStreet Ratings Team has this to say about their recommendation:

"We rate NATIONAL BANK OF GREECE (NBG) a SELL. This is driven by several weaknesses, which we believe should have a greater impact than any strengths, and could make it more difficult for investors to achieve positive results compared to most of the stocks we cover. Among the areas we feel are negative, one of the most important has been a generally disappointing historical performance in the stock itself." You can view the full analysis from the report here: NBG Ratings Report