Earlier this year Israel's Supreme Court ruled against the Church in a 14 year old case which looked at the purchase of properties at the entrance to the Christian Quarter of Jerusalem known as Jaffa Gate.
Churches in Jerusalem claim their presence in the holy city is under threat due to the legal ruling.
Church authorities say the buildings were sold by a rogue employee, who had no authority to do so, for $2.2m despite their estimated value of $6.7.
The employee, named as Nicolas Papadimas, has since fled the country.
The Church now says it has new evidence showing wrongdoing by the new owners Ateret Cohanim.
Announcing the legal action in a statement, the Greek Orthodox Patriarchate of Jerusalem said: "Despite the fact that the planned legal action by the Patriarchate is rare and difficult, and despite the fact that the judicial proceedings regarding the above mentioned properties have exhausted the Patriarchate for a decade and a half, the Orthodox Patriarchate of Jerusalem considers the Old City of Jerusalem a 'red line' and the core of the Christian belief, and the Patriarchate pledges that it will defend these principles and reclaim its properties; whether through judicial or diplomatic efforts, and in cooperation with the promoters of peace, joined by Christians around the world, protecting the Church heritage at the doors of the Holy Sepulchre and in the heart of the Christian Quarter. "
Calling for support from groups around the world, the statement said: "The Patriarchate calls upon the Heads of States and Heads of Churches around the world as well as on all those who strive for peace and justice in the Holy Land, to protect the historic and legal doctrine of the 'Status Quo', relating to the Holy Shrines, and to defend the Holy Sites from all underhanded and immoral dealings."
It's unknown when the legal action, calling on the court to reconsider its verdict, will be heard.
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