LONDON, UK — Step out of the train that whisks visitors from Heathrow Airport to Paddington Station and into the café across the street and you get an immediate introduction to today's London.
Although the fare is resolutely English, the guy preparing pots of Earl Grey tea and plates of scones with cream and strawberry jam is Spanish. The waitress bringing them to your table hails from Poland.
At a hotel in leafy Bloomsbury, the receptionist is Bulgarian. The trainer offering tips on burning calories in the nearby gym comes from Lithuania. Across town, a blue-uniformed guide answering tourists' queries at a famous museum is Italian.
More than 37 percent of London's population is foreign-born.
Since 2004, the United Kingdom has seen the arrival of over a million people from Poland, Lithuania and other countries in Central and Eastern Europe that joined the European Union that year.
In recent years, the numbers coming from recession-hit southern Europe have swelled.
British government figures show a 50 percent increase in Spaniards registering in the UK in the 12 months leading up to March. There's a 43 percent rise in Portuguese and a 35 percent increase in the number of Italians.
This is how the EU is supposed to work. The right of European citizens to live and work where they like within the 28-nation bloc is enshrined as one of the union's guiding principles.
Almost 60 percent questioned in a recent EU-wide poll said free movement of people was the EU's greatest achievement.
Gradually broadened since the 1960s, EU free-movement laws are designed to cut Europe's unemployment lines, bring skills to areas that need them and boost competitiveness by overcoming labor market inflexibility, which has long been blamed for holding back the European economy.
"The possibility to develop a truly European labor market is an opportunity," says Laszlo Andor, the EU's commissioner for employment, social affairs and inclusion.
"It is potentially a win-win game for individuals, companies, sending countries and receiving countries," Andor told a BBC interviewer recently. "We should anticipate more migration in the European Union, more citizens looking for a job in another country."
In the UK and other parts of northern Europe, however, the influx from the east and south is causing a backlash.
Tabloid headlines blame European migrants for a plethora of ills — from stealing local jobs to increased crime, and burdening health, education and welfare systems.
"Eastern European beggars spoiling London's smartest addresses," was a recent example from The Daily Express. "The EU simply won't allow us to stem the tide of immigrants," contended its rival, The Daily Mail.
Under pressure from the press and the increasingly popular, anti-EU United Kingdom Independence Party, Conservative Prime Minister David Cameron has announced that he intends to roll back the EU's free-movement ideals.
"Free movement within Europe needs to be less free," Cameron wrote in a recent Financial Times op-ed.
He suggested that citizens from poorer EU countries could be excluded from the free-movement provisions, richer members should be allowed to limit numbers of migrants from other EU countries and limit their rights to work or claim benefits.
"We must put in place new arrangements that will slow full access to each other’s labor markets until we can be sure it will not cause vast migrations," Cameron wrote.
The trigger for the concern is Romania and Bulgaria.
Both countries joined the EU in 2007, but older EU members were allowed a seven-year transition period before they have to open their doors to citizens from the bloc's two poorest members. That ends next year.
Although migration experts say most would-be migrants will head for Spain or Italy — where the languages are similar and there are already sizable Romanian and Bulgarian communities — many Britons fear an invasion.
Forty-seven percent of Brits want to keep restrictions that keep the Romanians and Bulgarians out, according to a November poll by the UK's Channel 5 TV station.
They’re not alone.
Far-right political parties from France, Austria and the Netherlands have seen poll support grow after switching their focus from traditional gripes over their countries' Islamic minorities to highlighting fears of a new influx of migrants from the east.
Dutch far-right leader Geert Wilders recently led a demonstration outside the Romanian embassy in The Hague, brandishing a "no entry" sign.
At EU headquarters in Brussels, Belgium, there are fears the anti-migrant propaganda could undermine one of the cornerstones of European unity by exploiting myths about the impact of the bloc's free-movement rules.
The entry into Britain of more than a half million Poles and a similar number from the other seven central and eastern European nations that joined the EU in 2004 caught many by surprise, but European Commission social affairs spokesman Jonathan Todd says their arrival has given the economy a boost.
"It’s estimated that the benefit to the UK economy was something like 1.2 percent of GDP as a direct result of the migrants from the EU eight countries because they basically helped to meet skills gaps and labor shortages," he said from Brussels.
"They create jobs because they take jobs that wouldn't be taken by host country workers, and then of course because they consume, they pay their taxes and so on, they actually contribute to the economy," he added.
Generally younger and fitter than the native population, migrants defy the "welfare scrounger" image portrayed in much of the British press, studies show.
"Britain’s EU immigrants are a boon, not a burden. They are young and more likely to be in work than Britons, and thus pay more in taxes than they take out in benefits and public services," said a report published in October by the Center for European Reform, a London-based think tank. "Contrary to popular opinion, EU immigrants are far less likely to take up benefits than the British population."
Although an estimated 14 million EU citizens now live in another member country, proportionally Europe's cross-border workforce is dwarfed by almost 10 to 1 by Americans who switch states for their job.
That mobility imbalance puts Europe at an international disadvantage, say those concerned that Cameron's plans represent a backward step for the EU economy.
"We shouldn't kid ourselves that we'll ever have the same amount of free movement in Europe as they have in the US, because there are language barriers, cultural barriers, whatever, but nevertheless, it can be part of the solution," Todd says. "We want to actively encourage more mobility between member states."
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However, even supporters of the EU's freedom of movement policies warn there have been abuses of the system — for example where migrants are exploited to avoid minimum wage and labor laws. A surge of foreign arrivals can place burdens on local authorities and trigger localized tensions.
"The social impacts of free movement have been uneven across the EU," says Elizabeth Collett, Director of Europe office of the Washington-based Migration Policy Institute.
"You don't know when and where they are going to arrive and that makes it very difficult for public service planning — how many hospital beds will you need? How many school places will you need?" she said in an interview from Brussels. "From that very pragmatic point of view, there are some very real concerns about how free movement is functioning and how to reduce those tensions."
Although the British may complain loudest, they’re far from the only ones to face such issues.
Over a million British students, workers and pensioners are estimated to be taking advantage of the free-movement rules to make their homes in another EU state — including around 760,000 in Spain, where they make up the second largest European migrant group, after some 1 million Romanians.