BRUSSELS - The prospect of Scottish independence is raising fears in Europe that it could inflame other separatist movements at a time when the continent's unity and even its borders are under threat, analysts say.
While nationalists from Catalonia to Flanders will watch Scotland's referendum with hope, Brussels is nervous about the possibility of a major European Union member like Britain falling apart.
The fear of contagion spreads as far as the EU's eastern frontier, where the Baltic countries worry that Moscow will back their ethnic Russian citizens who could then claim more autonomy.
But while the EU might initially make life difficult for a new Scottish nation, it would most likely allow it to join the bloc eventually, experts said.
"It is a very difficult situation for the EU if Scotland becomes independent, it really is," Pablo Calderon Martinez, Spanish and European Studies fellow at King's College London, told AFP.
The EU already has a lot on its plate as it tackles a stalled economy and high unemployment, and has insisted in recent days that the Scottish vote is an "internal matter." But European Commission chief Jose Manuel Barroso made the position clear in 2012: any newly independent country emerging from an EU nation would no longer be part of the bloc, and would have to reapply for membership.
Barroso outraged nationalists in February when he said it would be "extremely difficult" for Scotland to gain automatic membership, comparing it to Kosovo, which broke away from Serbia.
European Council president Herman Van Rompuy meanwhile weighed in on Catalonia in December, saying he was "confident" Spain would remain "united and reliable."
Van Rompuy is a former premier of Belgium, which is deeply divided between his own Flemish -speaking north and a Francophone south.
International clout at risk
Independence movements are a threat to the nation states that "fund the activities of the EU," said Montserrat Guibernau, professor of politics at Queen Mary University of London.
Spain fiercely opposes Catalan plans to vote on independence, a campaign that brought nearly two million people onto the streets of Barcelona Thursday. The Basque region between Spain and France also remains very sensitive.
Paris and Madrid opposed the break-up of Yugoslavia in the 1990s and would "probably use whatever clout they have in the EU to make life difficult for Scotland to teach Catalonia a lesson," Calderon-Martinez said.