Now, a row in the country over data supplied by its official statistics agency Elstat could risk Athens' current bailout programme.
Earlier this month Greece’s Supreme Court ruled the former head of Elstat, Andreas Georgiou, should face trial on charges of artificially inflating Greece’s deficit in 2009 to help foreign creditors secure a better deal.
The head of the European Commission's data agency Eurostat, Marianne Thyssen, has told reporters Georgiou effectively had no case to answer.
For the Commission and Eurostat it is absolutely clear that data on Greek government debt during 2010-2015 have been fully reliable and accurately reported to Eurostat – unlike the situation before this period. It is necessary to get the record straight and avoid misinterpretation because this could be very dangerous.
Thyssen said the Greek government must "actively and publicly challenge the false impression that data were manipulated during 2010-2015 period and to protect Elstat and its staff from such unfounded claims" and the situation could damage the credibility of the Greece with international creditors.
The Greek debt crisis was sparked in 2009 when budget calculations projected a doubling of its deficit to over 12 per cent of gross domestic product (GDP).
Then, under Georgiou's leadership, Elstat said the deficit for 2009 had in fact been over 15 per cent of GDP.
Greece's European and IMF creditors demanded a politically independent statistics service as part of Greece’s 2010 bailout overhauls.
The Greek government has issued a response saying it was "surprised" at the EC's comments.
Greek government spokeswoman Olga Gerovasili said in a statement:
In its letter the Commission states its standard principle to not comment on cases pending in the justice system, a principle which is shared and followed by the Greek government.
Georgiou, who ran Elstat through the height of the Greek and Eurozone debt crisis, has denied the charges, which carry a prison term of up to 10 years. Two other Elstat officials also face charges.
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