Der Spiegel reports that five separate ministries gave the okay for the project, including the tourism ministry.
The video is a recording of Kostas Stavropoulos, the 'voice of Greece', reporting on the German occupation in April 1941 just hours before the Wehrmacht (Nazi armed forces) reached Athens.
“The German attackers have reached the outskirts of Athens,” he warned. “Brothers and sisters beware, in a few minutes Radio Athens will no longer be Greek. It will be German and only tell lies.”
The accompanying black and white footage shows German military vehicles with armed soldiers inside.
The video in the underground network - which reaches an estimated 1 million people per day - is the most recent evidence of a strategy put forward by the Greek defence ministry in March, according to which Greek awareness of Nazi war crimes should be strengthened, writes Spiegel.
In March the Greek prime minister Alexis Tsipras called for Germany to pay reparations for war crimes committed by the Wehrmacht during the occupation of Greece and as repayment for a loan forcibly levied by Berlin in 1942.
A study commissioned by the Greek government puts total reparations in the region of €332 billion. Many commentators have noted that this sum would pay off a large amount of the debt Athens currently owes to its financial creditors.
Tsipras optimistic ahead of Monday summit
The Greek government's debts will once again be discussed by European finance ministers when they meet in Brussels on Monday.
Speaking in the Greek parliament on Friday Tsipras said he was optimistic an agreement could be reached during the meeting.
He said that there are no technical issues blocking an agreement beneficial to all parties. The result of the meeting “depends on the political will” of Athen's EU partners, he said.
His government, Tsipras claimed, “is doing everything it needs to do” in order that a “concrete solution” can be found.
But in Brussels there is a great deal of scepticism as to whether a deal can be reached any time soon.
German finance minister Wolfgang Schäuble said on Thursday: “My expectations are not very high.”
“One shouldn't expect any spectacular result. That isn't in the realm of possibility,” finanztreff.de reported him as saying.
Without an agreement of the reforms Athens is to carry out domestically, Greece's creditors are refusing to release a further €7.2 billion in loans.
According to media reports Greece is close to bankruptcy and a quick agreement is crucial.