European freedom of movement rules: EU reaction to UK plan
17 January 2014 Last updated at 14:39 GMT
Being able to travel freely to live and work in any country across the European Union was a founding principle of the Treaty of Rome.
David Cameron has suggested there should be limits to the freedom of movement of European citizens after poorer countries, such as Romania and Bulgaria, joined the EU in recent years.
Jo Coburn reports from Strasbourg for Politics Europe on the European reaction to the British bid to take more control of its borders.