Immigration is a well-documented headache for British politicians. According to various polls it is the biggest issue facing the UK, trumping even the NHS, the closest thing Britain has to a national religion.

Immigration is constantly brought up on the doorstep by voters who swing both left and right, and opposition to unlimited migration from Europe is what underpins a vast section of the Eurosceptic movement: the Tories know it, Labour knows it, the Lib Dems are soon to be irrelevant and only UKIP is willing to address it.

Pushed heavily by public opinion, the Eurosceptic fringe of his own party and the ever-increasing threat from UKIP, Tory leader David Cameron has cautiously committed to an in-out EU referendum, notably not within this parliament and only if he secures a parliamentary majority at this year’s General Election, which he won’t.

Prior to giving the British people their long awaited say in the future of our country, however, Cameron will first try to renegotiate the terms of our membership of the EU based on seven major changes including new controls to stop “vast migration” across the continent, tighter immigration rules and benefit restrictions for new migrants, less red tape and abolishing the principle of “ever closer union” among EU member states.

He hopes to push through enough minor changes to create enough major headlines that the people will be mollified, the sceptics appeased and suitably quietened, so that the whole messy business of a referendum will go away.

And yet Germany’s Chancellor, Angela Merkel and other leading EU figures have repeatedly ruled out any treaty changes that might affect freedom of movement of people, the biggest concern of the British electorate, rendering any small changes pretty damn meaningless to most who care. Merkel has gone so far as to say that she would rather see Britain exit the EU than compromise over the “fundamental principles of free movement in the EU”, such is Germany’s commitment.

But it seems that on matters of immigration and free movement of people Merkel does not speak for the country she governs.

Immigration is proving to be a headache for Merkel on two fronts as the anti-immigration PEGIDA movement continues to grow, attracting 25,000 people to a recent march in Dresden all the while the Eurosceptic party, Alternative for Germany (AfD), that cost Merkel’s Christian Democratic Union (CDU) party heavily in recent local and European elections continues to snap at her heels. The AfD, like UKIP, has moved its focus from purely issues directly relating to the Euro and EU constitutional matters to migration, which is intrinsically linked to EU membership, and voters are reacting.

Immigration into Germany in the first half of 2014 alone was an eye-watering 667,000 people, a 20 percent increase on the previous year. Now that Merkel is being threatened by the AfD, she seems somewhat less committed to the free movement principle; UPI reports that now German politicians are trying to determine how to react to the immigration surge, with one borrowing a policy from UKIP by suggesting the creation of a point system to hire skilled immigrants. Deportations, too, reached an eight-year high, with a total of 10,884 people deported from Germany last year.

If Germany is thinking of adopting a points system this will have massive ramifications across the European continent. However, what is good for the German goose must therefore be good for the long suffering British gander; just because Merkel essentially runs the EU does not mean that she can think faster and act with greater ruthlessness while telling Cameron to go hang if he wants the same leeway.

The simple fact is that as so often Germany is the essential European Nation. When it says no, then nothing happens. When it says maybe, plates begin to move, and when it says Yes, any previous opposition is erased from memory and change happens.

Migration, as the horrific pictures coming out of the Mediterranean over the last week make absolutely and painfully clear is not just a problem for the UK, but also a problem for the greater European continent. The rules of free movement, designed in the heady days of the 60’s when all EEC countries were of a similar economic and social development are no longer fit for purpose. Sooner or later what is now a fundamental principle carved into the tablets of the Treaty of Rome, will become an accident, a footnote in history. This will happen when Germany decides it should.

Looking at the noises out of Berlin that moment might be far sooner than anyone thinks.