Alexander Smith: Why immigration may open up cracks in the coalition

This was followed by Vince Cable's moment of hubristic claim that his resignation could single-handedly bring down the Government, which appeared to underscore how estranged relations amongst Government Ministers had become.

But what new fault lines will emerge among coalition MPs this year?

Apart from Europe, immigration is probably the one issue on which the ocean of difference between the Conservative and Liberal Democrat election manifestos in May 2010 was greatest.

While the Tory Party promised tight restrictions on immigration, the Liberal Democrats were proposing what some described as an amnesty for illegal immigrants currently resident in the UK.

Many Conservatives derided this policy at the time, although it did enjoy the support of some notable Tories, including the London Mayor Boris Johnson.

To reach agreement on entering a coalition with the Conservatives, the Liberal Democrats had to give way on most of their manifesto commitments on immigration. As the new Parliamentary year begins, there is already anxiety on the backbenches of both parties..

In 2008, over 500,000 people came to the UK. This amounts to approximately 200,000 more people than the number that left our shores last year. When these figures are broken down, it becomes clear that the Government has its work cut out if it wants to achieve its goal of reducing net migration to the UK.

For instance, approximately 15 per cent of those coming to settle in the UK are expatriate Britons who have decided to return home to their country of birth. A third of all other arrivals hail from the European Economic Area (EEA).

The Government is legally powerless to prevent the entry of both these groups of people to the UK.

This leaves a figure of about 280,000 people arriving from the rest of the world. And it is these people that the Government hopes to target in the coming months.

From April 2011, the coalition Government will lower the cap on the number of migrant workers from outside the EEA allowed to enter the UK to 21,700.

This is a cut of 6,300 from 2009. Of this number, 20,700 will be Tier 2 skilled migrants, graduates entering the UK with job offers and sponsorship. But 1,000 will be allowed into the country through a new "exceptional talent" route. They will be academics, artists, scientists and writers.

Of course, these numbers seem pretty arbitrary and there have been critics of the Government's cap, not least from UK businesses who fear that it will send a counter-productive message to the world that Britain is closing its borders to skilled migrants.

These numbers also seem like a drop in the ocean given the overall figures. Many have suggested that cutting the number of migrant workers will have a negligible impact on slowing the rate of migration to the UK.

But the problem for the Government is that it has few policy mechanisms for really tackling immigration. For example, about 20 per cent of non-EEA migration includes families being reunited with loved ones from abroad. Enforcing policies that break up immigrant families would contravene human rights law so there is very little the Government can do to restrict such migration.

Making up 60 per cent of those coming into the UK from outside the EEA, international students are by far the largest group of migrants whose movements the Government might seek to restrict.

The Home Secretary Theresa May stated last year that she is looking at ways of curbing these numbers, although she has insisted that students will be allowed into the country if they are studying for degrees or going to "highly trusted" colleges.

However, it is difficult to fathom how such restrictions might be introduced without dramatically damaging universities and colleges that rely on international students as important sources of income.

Given the massive funding cuts it has introduced to further and higher education in the UK, the stakes for the Government if it blunders on this issue are all the more higher.

After the USA, more international students come to study in the UK than any other country. They are attracted to our shores because they want to learn English and gain qualifications that are recognised around the world. This is the clearest evidence of the high esteem in which the rest of the world holds British universities.

The political wounds the Government inflicted on itself during the vote on university tuition fees last year are still fresh and weeping.

It will be fascinating to see how coalition Ministers seek to cut international student numbers if it means risking rubbing salt into those wounds and inspiring fresh resistance from backbench Conservative and Liberal Democrat MPs alike.

Dr Alexander Smith is a sociology lecturer at the University of Huddersfield.