THESSALONIKI (AP) — Police in northern Greece have used tear gas and water cannon to disperse anti-government protesters opposed to a proposed agreement with neighbor FYROM that would end a decades-long name dispute.

The protesters challenged a heavily patrolled police cordon late Friday in the northern city of Thessaloniki where left-wing Prime Minister Alexis Tsipras spoke to supporters in a televised address.

Under the proposed deal, Greece’s neighbor will change its name to “North Macedonia” and Athens would drop its objections to the country’s accession to NATO and eventually the European Union.

Opponents of the agreement, including the opposition conservatives, argue that it would fail to safeguard Greece’s ancient Macedonian heritage and would pose a potential threat to its territory.

A man holding a Greek flag shouts slogans during a rally in front of the White Tower, a landmark of the northern Greek city of Thessaloniki, Friday, Dec. 14, 2018. (AP Photo/Giannis Papanikos)

A woman holding a religious icon shouts slogans in front of riot police during a rally in the northern Greek city of Thessaloniki, Friday, Dec. 14, 2018. Hundreds of people protest against government efforts to end a three-decade-old dispute with neighboring Macedonia as the Greek Prime Minister Alexis Tsipras will deliver a speech to party cadres and supporters. (AP Photo/Giannis Papanikos)