Campaigning officially began in Macedonia on Monday for a Sept. 30 referendum on changing the country's name, a move which would allow the Balkan country to qualify for NATO membership and also pave its way toward the European Union.

Macedonians will vote on a proposal to change the former Yugoslav republic's name to North Macedonia, in a bid to end a long-running dispute with neighbor and NATO member Greece which saw use of the term "Macedonia" as a claim on its own province of the same name.

The proposed change met with fierce criticism in the two countries, with opponents on both sides accusing their governments of conceding too much to the other country. Macedonian parliamentary Speaker Talat Xhaferi recently urged politicians to conduct their campaigns "transparently, directly, without discrimination, prejudice and with respect of every citizen."

The question voters will be called to decide on is: "Are you in favor of membership in the European Union and NATO by accepting the deal between Republic of Macedonia and Republic of Greece?"

Polls indicate Macedonians will likely back the deal, but it remains unclear whether turnout will meet the required 50 percent threshold for the vote to be valid.

Western leaders who visited Macedonia last week, including German Chancellor Angela Merkel, have urged Macedonians to back the deal.

"This is a historic chance that a generation has only once. Don't stay at home: Seize the democratic opportunity to say what you think about the future of your country," Merkel said last week at a joint news conference with Macedonian Prime Minister Zoran Zaev.

NATO Secretary-General Jens Stoltenberg has also urged Macedonians to approve the deal with Greece, noting it is the only way for the country to join NATO.

"The idea that there is an alternative way where you can reject the name agreement with Greece and join NATO is an absolute and total illusion," Stoltenberg warned.

The main conservative opposition VMRO-DPMNE party and Macedonian President Gjorge Ivanov have repeatedly said Macedonia's strategic goal is to join NATO and the EU, but that they oppose the deal with Greece, warning it will damage the country's national interests.

Zaev, for his part, has expressed optimism on the outcome of the referendum.

"The European Union and NATO are ahead of us. That is our goal on this last section of the road that we build together since our independence," Zaev said during a rally in the town of Bitola late Sunday, before the official start of campaigning. "This is our future, this is our choice and your decision on Sept 30 will secure our place in the EU and NATO."

A total of 64 smaller political parties and civic associations are campaigning against the deal, joining together in an opposition front called "Macedonia is boycotting."

The agreement with Greece was signed in June, and also requires changes to the Macedonian Constitution. The final step for the country to join NATO would be ratification of the deal by Greece's parliament, which would vote only after Macedonia has completed all of its necessary procedures.