"They made their calculations and said each German owed 875 euros for what Greece had to pay during World War II."
He added that they chose his town "because it was the first capital of Greece in the 19th century."
Greek news website News247.gr said the couple made their calculations based on the amount that Greece was forced to pay Germany during the war.
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In 1942, Greece was made to pay Germany a "maintenance loan" – also known as an "enforced loan" – of 476 million Reichsmarks.
The couple estimated that, with interest, this would be worth around 70 billion euros today, local media reported. Dividing that figure by the German population – just over 80 million people – they arrived at the sum of 875 euros.
The couple reportedly said at a press conference that they did not have enough money to pay for two people.
The German couple's offer has made them local heroes in the town of Nafplio, hailed for their solidarity and generosity. The money was donated to a local charity that offers free food to members of the community who are struggling financially.
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The reports come as Greece's long-standing calls for compensation from Germany for the Nazi occupation of the country return to the fore.
Last week, Greek Prime Minister Alexis Tsipras accused Germany of using "legal tricks" to get out of paying reparations. Speaking to the Greek parliament, he said, ""Germany has never properly paid reparations for the damage done to Greece by the Nazi occupation."
However, Germany has repeatedly rejected calls for compensation, saying its reparations covered the "maintenance loan" and it has honored all of its war obligations. For example, the country made a payment of 115 million deutschmarks (59 million euros, or $62 million) to Greece in 1960, according to Reuters.
Greece is in the midst of a financial struggle, battling loan repayment deadlines and growing debt pile.
The country's two financial bailouts, worth a total of 240 billion euros, have been the source of public anger in Greece and relations between the country and its international creditors have become increasingly tense, particularly with Germany, the main driver of austerity measures.