By Paul Kirby
EU reporter, BBC News
Ever since Macedonia gained independence in 1991, its name has been the subject of a bitter dispute with southern neighbour, Greece.
Protesters have taken to the streets in both countries
Now, the name of the former Yugoslav republic could jeopardise its bid to join the EU and Nato.
In a progress report, the EU said on Wednesday that Macedonia could still make enough progress this year to begin accession negotiations.
The only problem could be its name.
In the words of EU Enlargement Commissioner Olli Rehn: "If we can't settle this issue, I'm afraid it will have negative ramifications [for EU accession]."
Macedonia is already the name of a northern Greek region and Greeks are angry that the former Yugoslav republic has linked its heritage to Philip of Macedon and Alexander the Great.
They argue that taking its name inherently suggests territorial ambitions beyond their neighbour's existing borders.
Until now the dispute has been papered over with a manufactured deal allowing the Macedonians to sit in the United Nations under the name Fyrom, former Yugoslav republic of Macedonia, whose capital is Skopje.
The Republic of Macedonia exists constitutionally and has been recognised by much of the international community, although many countries including the UK use the name Fyrom in international organisations.
But when it comes to joining the European Union and Nato, Greece, as a member of both, has the power of veto. A unanimous vote is necessary before new members are allowed in.
Macedonia is already a candidate for EU membership and the European Commission has announced that, despite two years of slow movement, the necessary progress towards a start-date for accession talks could be made by the end of 2008.
Nato foreign ministers considered Macedonia along with Albania and Croatia at a meeting in Brussels on Thursday, with a view to inviting them to join the alliance at a summit in Bucharest in April.
The three countries are already members of Nato's Membership Action Plan, paving the way for possible membership.
Greece has no problem with Albania and Croatia, but it is digging in its heels over its northern neighbour.
Macedonian Foreign Minister Antonio Milososki told the BBC News website his country's soldiers had already played their part in Afghanistan.
"If other Nato countries, including Greece, do not mind when our soldiers employed in Afghanistan wear on their uniforms the name of our country, Macedonia, and our flag why would Greece mind if we joined the alliance after we have fulfilled all the relevant criteria?"
That argument is rejected by Nikos Karahalios, campaign manager of Greece's ruling New Democracy party, who says simply that Greek public opinion will not accept another Macedonia.
"It might sound very sentimental but it is embedded in the hearts and minds of Greeks," he says.
"I think [Greek Prime Minister Costas] Karamanlis has no other option than to wield the veto. The stance of the public will not let us back down."
UN envoy Matthew Nimetz has been busy negotiating in search of a name acceptable to both sides.
But five names he proposed were turned down in February. Reports suggest Athens was happy with "Republic of Upper Macedonia" but Skopje was not.
The other four names he suggested were: Independent Republic of Macedonia, New Republic of Macedonia, Democratic Republic of Macedonia and Constitutional Republic of Macedonia.
Greece has been a Nato member for 55 years
Mr Nimetz has been holding further talks in the two capitals, but passions on both sides of the border are high.
Thousands of people protested in Skopje at the end of February because of a possible name change and there have been similar demonstrations in Thessaloniki, the capital of Macedonia in northern Greece.
As far as Nato is concerned, Mr Karamanlis has made it clear that the problem lies with Macedonia.
After talks with Nato Secretary General Jaap de Hoop Scheffer on Monday, he said: "As long as the neighbouring country persists in a position of intransigence, the answer is 'no solution means no invitation'."
Mr Milososki says Macedonia has already bent over backwards, first by changing its flag in 1995 and then by amending its constitution to specify no territorial aspiration against any neighbour, particularly Greece.
On Thursday, his government produced a two-page advertisement in the UK's Times newspaper, objecting to Greece's position and listing 30 reasons for Nato membership.
Mr Karahalios says Greeks are unconvinced by their neighbour's assurances: "We have seen proof that they are cultivating the feelings of irredentists. Official maps come every now and then out of their foreign ministry which include Greek soil."
The Macedonian government also has to consider public opinion on an issue which its foreign minister describes as "the cornerstone of our nation".
"I would like to see how prepared Greece would have been if we were speaking about the constitutional name of the Republic of Greece," says Mr Milososki who insists his government is prepared for a bilateral compromise.
In 1995, Athens agreed not to let its northern neighbour's name prevent it from joining international organisations.
Now that the former Yugoslav republic is knocking on the door of two more, it may be left to the organisations themselves to find a way out.