Demonstrators in Greece are planning a massive rally Sunday to protest a deal that would normalize Greek relations with Macedonia.

Greeks have been divided over the deal, in which Macedonia will change its name to the Republic of North Macedonia and Greece will drop its objections to the Balkan country’s joining NATO and the European Union.

The U.S. State Department said in a tweet Friday that Sunday’s demonstration in Athens is expected to draw 150,000 or more participants.

Greek identity

Greek protesters say Macedonia’s new name represents an attempt to appropriate Greek identity and cultural heritage. Macedonia is the name of Greece’s northern province made famous by Alexander the Great’s conquests.

Opposition to the deal is particularly strong in the Greek province of Macedonia, where many people have put up posters urging local lawmakers to vote against the agreement.

A nationwide poll in Greece this week found that 70 percent of respondents oppose the deal.

The agreement has caused Greek Prime Minister Alexis Tsipras to lose his four-year coalition in parliament after his nationalist allies defected to protest the deal. Following the upheaval, Tsipras narrowly won a confidence vote in parliament Wednesday.

Tsipras has called for a televised debate on the planned name deal with Macedonia before parliament votes on the agreement.

The Greek prime minister and his Macedonian counterpart, Zoran Zaev, brokered the compromise in June to end a 27-year name dispute between the two neighbors.

​Macedonia approves

Last week, Macedonia’s parliament approved a constitutional revision to change the country’s name. The agreement has also caused protests in Macedonia, with critics there saying the government gave up too much in the deal.

Tsipras has argued the Macedonia deal will bolster stability in Europe’s Balkan region. European Union countries have also strongly backed the deal.