Here is a look at the push for independence in some members of the 27-nation European Union.
CATALONIA: Spain's parliament voted last month to block the northern region of Catalonia from holding a referendum on independence. It was the latest development in a growing political battle between Barcelona and Madrid in the midst of an economic downturn which has fuelled separatism. With its own language and distinct culture, Catalonia has a population of 7.5 million. However, Spain said last weekend Catalonia would soon receive 3.3 billion euros ($4.19 billion) from a liquidity fund set up to help the country's regions repay their debts.
BASQUE COUNTRY: With a population of 2.1 million, the region raises its own income and corporate taxes unlike most of Spain's 17 highly devolved autonomous regions which receive transfers from the central government. Like Catalans, the Basques have their own language and culture. The Basque separatist group ETA, responsible for decades of violence, announced in October 2011 a "definitive cessation of armed struggle".
SCOTLAND - Britain's prime minister flew to Scotland last month and finalised a deal to allow Scotland to decide in a 2014 referendum whether it should become independent. With only 5.2 million people, Scotland has been in a union with the rest of Britain for 305 years. But since the Scottish National Party won elections the push for independence has grown.
FLANDERS: With a population of 6.2 million, Flanders constitutes the northern half of Belgium with Brussels as its capital. The self-governing Flemish Region was created during the federalisation of Belgium, largely along linguistic lines, in the 1980s and 1990s. Its elected government has authority over a wide range of policy areas such as agriculture, transport and foreign trade. With thriving industries, including car manufacturing, chemicals and pharmaceuticals, its jobless rate is about half that of French-speaking Wallonia in the south.
ITALY-PADANIA: Italy's Northern League was founded to try to separate Italy's more industrialised, prosperous north from its more impoverished south to create a new region called "Padania". The League is the staunchest opponent of Prime Minister Mario Monti's austerity measures and has often criticised European Union institutions.
Sources Reuters/here ($1 = 0.7871 euros)