More than 1.6 million migrants moved to Britain from within the EU in less than a decade.
The astonishing figure – the equivalent to the populations of Manchester and Birmingham combined – settled here between 2006 and 2014, according to the UK Statistics Authority.
It means an average of 500 people every day for nine years exercised their right to free movement – adding to the pressure on Britain’s schools, hospitals and other infrastructure.
More than 1.6 million migrants moved to Britain from within the EU in less than a decade, as migrants in Calais continue to try to make their way into the country
And with migration from within the EU continuing to run at record levels over the past two years, the true total now will be even higher.
Campaigners said the figures showed that, if Britain wants to control its borders and plan properly for the future, it must quit the EU.
It follows revelations of how the free movement rules have let dozens of foreign criminals commit horrific offences in Britain.
In a speech today, Justice Minister Dominic Raab will warn that the ‘unyielding’ edict is also giving a ‘free pass’ to extremists and terror suspects.
Mr Raab will say that, where the UK has ‘sketchy intelligence’ that somebody may be linked to terrorism, the bar for denying them a right to free movement is set so high that we have to let them in.
The migration figures were compiled by the statistics authority following a request by eurosceptic Tory MP Anne Main.
In 2014 alone, 287,000 people from within the EU – many from Eastern Europe – settled in Britain. Separate figures compiled by the United Nations suggest there are now 2.9 million EU nationals living in Britain.
By comparison, there are 1.2 million Britons living in other EU countries.
Employment Minister Priti Patel said: ‘These levels of immigration are far too high for this country to sustain.
With housing, schools and the NHS all under pressure, this country will not be able to cope with the demands from further waves of migration on this scale from the EU.
‘While the UK remains a member of the EU we are powerless to stop or control the numbers coming in. We can only take control of our immigration policy and our borders by voting to leave the EU.’
Mrs Main told the Mail: ‘These figures are alarming because they don’t take into account all immigration from the EU.
‘This is the choice faced by Britain on June 23: from today until the polling day, the UK will need to find housing, hospitals and schools to accompany a new town the size of Canterbury, Torquay or Folkestone.’
Earlier this week, a dossier compiled by the Vote Leave group listed 50 of the ‘most dangerous’ European criminals who have entered the UK freely, despite convictions in their countries.
Once here, 45 of them committed serious offences. In total, they were responsible for 14 killings, including nine murders, and 13 sex crimes. They included Arnis Zalkalns, the Latvian who murdered his wife before moving to the UK where he killed 14-year-old Alice Gross.
In his speech, Mr Raab will say: ‘The elephant in the room is the unyielding principle of free movement across Europe’s borders and its impact on Britain’s security.
‘Yes, we have checks at the border because we’re not in Schengen. But, what good are checks if we can do so little to act on them?
‘We cannot require those arriving from other EU countries to have a permit issued by the UK, given the scope for fraudulent documents to be issued in other states.
‘We cannot refuse entry to EU citizens producing an EU passport, even though we have no control over the checks made by the country of issue, which we can charitably say are of mixed reliability.
‘Crucially, for UK intelligence agencies, we cannot bar individuals on whom we have sketchy intelligence but reason to believe may be linked to terrorist-related or other serious criminal activity.
‘In most countries outside the EU, you can bet that individuals flagged in this way would not waltz through passport control without these doubts or question marks being answered or assuaged.’
The figures on people moving to the UK from the EU will intensify demands for ministers to publish full figures on who is here – with many MPs claiming the total is being undercounted by the Office for National Statistics.
The row centres on a massive gap between two sets of figures relating to immigration.
ONS figures – the basis for the research by the UK Statistics Authority – show that 904,000 EU migrants have arrived in Britain since June 2010. But in the same period, officials have issued 2.2 million National Insurance numbers to EU migrants.
Experts say that, in order to find out who is actually here, the Government should release the amount of NI numbers which are currently ‘active’, meaning migrants are using them to pay tax or receive benefits.
A Home Office spokesman said: ‘In the past our benefits system has been a magnet to EU migrants and that is why through our renegotiation we have put an end to the something for nothing system.
‘If we left the EU but wanted access to the single market we would have to accept free movement whilst losing our influence in deciding the rules.
‘We want Britain to have the best of both worlds – ensuring we only pay benefits to those who have paid into the system whilst keeping access to the single market of 500 million people which secures jobs and financial security.’
Nick Herbert, chairman of Conservatives In and a former police minister, said: ‘We should take no lectures from the Brexit campaigners who oppose all the EU co-operative measures which help to keep us safe.
‘They oppose the European Arrest Warrant which brings serious criminals to justice and they oppose EU measures to share DNA records which identify offenders.
‘They are willing to place their ideological opposition to any EU co-operation ahead of effective security measures.
‘The UK is outside Europe’s passport-free Schengen area, we have border controls and checks, and we can and do turn away people who pose a threat to our country. It is simply irresponsible to suggest otherwise.’