Greek Prime Minister Alexis Tsipras was accused on Wednesday of surrendering part of his nations identity following a historic deal ending a decades-long dispute between Greece and Macedonia over the latters name. Under the agreement announced by Athens and Skopje on Tuesday, the Balkan state known as Former Yugoslav Republic of Macedonia" would henceforth be called the "Republic of Northern Macedonia". The head of Greeces Conservative New Democracy, the main opposition party, criticized the deal, describing it as "deeply problematic." Kyriakos Mitsotakis called on Greeces president Wednesday to intervene so the deal can be debated in parliament before it is signed, instead of after. He said the majority of Greeks were against it and Tsipras lacked the political legitimacy to sign it. "We are in a situation that is unprecedented in Greeces constitutional history. A prime minister without a clear parliamentary mandate willing to commit the country to a reality which will not be possible to change," Mitsotakis said. The agreement is expected to be signed this weekend. Greek Defense Minister Panos Kammenos, whose right-wing Independent Greeks party is the coalition partner in Tsipras government, said he would oppose an agreement in the parliamentary vote. This would leave the left-wing prime minister dependent on support from political opponents to ratify the deal in parliament. The name dispute has soured bilateral relations since 1991, when Greeces northern neighbor declared its independence from former Yugoslavia under the name Republic of Macedonia. At the time Greece argued that the term "Macedonia" implied a claim on the territory and ancient heritage of its own northern province of the same name.