Macedonia’s president said on Wednesday he would not sign a landmark deal reached with Greece on changing his country’s name, dashing hopes of a swift end to a diplomatic dispute that has blocked Skopje’s bid to join the European Union and NATO.

Axar.az reports quoting Reuters.

In Greece too, Prime Minister Alexis Tsipras faced a barrage of criticism and the prospect of a no-confidence vote against his government after he and Macedonian Prime Minister Zoran Zaev announced the accord late on Tuesday.

Under the deal, Macedonia would become formally known as ‘the Republic of Severna (Northern) Macedonia’. It is currently known officially at the United Nations as the ‘Former Yugoslav Republic of Macedonia’.

Athens has long objected to its northern neighbor’s use of the name ‘Macedonia’, saying it implies territorial claims on a northern Greek province of that name and also amounts to appropriation of Greece’s ancient cultural heritage.

“My position is final and I will not yield to any pressure, blackmail or threats. I will not support or sign such a damaging agreement,” Macedonian President Gjorge Ivanov told a news conference in Skopje.

Ivanov, who is backed by the nationalist opposition VMRO-DPMNE, can veto the deal. Macedonia’s center-left government also needs a two-thirds majority to win parliamentary approval and this would require the backing of VMRO-DPMNE, which is strongly opposed to the accord.

The president also said Macedonia’s possible future membership of the EU and NATO was not sufficient excuse to sign such a “bad agreement”.

The accord must be approved by Macedonians in a referendum as well as by the parliaments of both countries.