FYROM (Macedonia) is looking at four options to settle a decades-long dispute with Greece over its name, Prime Minister Zoran Zaev told Reuters in an interview on Tuesday.

The small ex-Yugoslav republic and its southern neighbor Greece have agreed to step up negotiations this year to resolve the dispute, which has frustrated Skopje’s ambition to join NATO and the European Union.

Athens, which like all members of both organizations has a veto over admissions, objects to the use of the name Macedonia, arguing that it, along with articles in Skopje’s constitution, could imply territorial claims over a northern Greek region of the same name.

Macedonia hopes the issue can be resolved in time for an EU meeting in June and a NATO summit in July, and is proposing a geographical “qualifier” to ensure there is clear differentiation in the two names.

“The suggestions are Republic of North Macedonia, Republic of Upper Macedonia, Republic of Vardar Macedonia and Republic of Macedonia (Skopje),” Zaev said in a television interview after attending a summit on the Western Balkans in London.

Asked whether Greece would be happy with one of these options he added: “Yes … they have more preferred options and some not so preferred options [in terms of the name].”

He said the question that remained was whether there was “a real need” to change Macedonia’s constitution, something Greece had also asked for in recent months.