A wave of unrest sweeping across North Africa has raised alarm in the European Union about the possibility of a flood of illegal immigrants arriving in Europe in search of security and welfare.
EU governments are stepping up a debate on how to tackle the issue at a time when European voters have become more hostile to foreigners because of the economic downturn.
A series of short-term measures will be considered to stem the tide of migrants in the coming weeks. In the longer term, concerns over renewed migration pressure are likely to weigh on EU plans to reform its creaking asylum system.
Following is an overview of immigration policies and challenges in the bloc of half a billion people.
WHO ARRIVES IN EUROPE?
Thousands of migrants have already fled their home countries as a result of anti-government protests, particularly in Tunisia and Egypt. More than 5,000 Tunisians and dozens of Egyptians have arrived in Italy, an important EU port of entry, in recent weeks.
Thousands could cross Libya into the EU if veteran leader Muammar Gaddafi fulfils a threat he made in the past week of ending cooperation with the bloc on stemming the flow of migrants.
Some EU diplomats have dismissed this as posturing but Libya has played an important role in stopping many of Africa's poor from crossing into the EU.
According to the International Organization for Migration (IOM), about 1.5 million undocumented migrants live in Libya, mainly from sub-Saharan Africa, Egypt and the Horn of Africa. IOM experts say about 10 percent hope to move to Europe.
Recent arrivals from north Africa are only a fraction of the number seeking refuge in Europe each year.
In the past 12 months, roughly 100,000 people have crossed into the EU illegally, mostly through the bloc's southern borders. Turkey is the most frequently used illegal crossing point into the EU, through its border with Greece.
In the same period, 250,000 people were seeking asylum in the EU, with more than a quarter arriving from Afghanistan, Russia, Somalia and Iraq. Countries that received most asylum applications were France, Germany, Sweden, Britain and Belgium.
Currently, one in 10 people living in Europe is an immigrant, with Germany hosting the third largest immigrant population in the world after United States and Russia.
EU IMMIGRATION POLICIES
Each EU member state has its own immigration and asylum regulations and standards. Some common rules exist and the EU's executive, the European Commission, says more harmonization is needed in the approach to immigrants.
In particular, the Commission wants to ensure all EU governments adhere to the same standards when caring for refugees, for example when it comes to housing, access to jobs and detention rules.
It also wants to change rules determining which governments are responsible for migrants. Under current regulation, migrants should seek asylum in the country that was their first port of entry into the bloc.
However, many people take advantage of borderless travel in the EU to file applications in other countries known for better asylum conditions. Many are sent back to Italy or Greece to apply. Human rights organizations have said conditions in Greece often contradict international standards on protection.
Countries such as Greece and Italy argue others should shoulder more of the burden of immigration. Some states also would like to see more joint efforts in securing EU borders.
(Sources: European Commission, Eurostat, International Organization for Migration, Frontex)
(Reporting by Justyna Pawlak; Editing by Andrew Dobbie)