Most Britons want to see immigration reduced, but think the Government should focus on cutting the number of illegal immigrants and asylum seekers instead of foreign students and skilled workers, a survey showed today.
Half of those who want to see immigration reduced said most or even all of the cuts should come from among illegal immigrants, research by Oxford University's Migration Observatory found.
And of the three in 10 people who do not want to see immigration cut, three fifths still want to cut the number of migrants in the UK illegally, with two-fifths feeling strongly about this.
David Cameron appealed for the public to "shop" illegal immigrants last Monday as he pledged to reclaim Britain's borders, urging Britons to help tackle the issue by reporting suspicious individuals.
The Government has pledged to cut net migration from the current 242,000 to the "tens of thousands" last seen in the 1990s, with crackdowns on forced and sham marriages, bogus students and an annual cap on immigrants coming from outside the EU.
But the Migration Observatory report showed foreign students, which make up almost two fifths of all immigrants to the UK, appear to be of little concern to Britons with just a third wanting cuts to come from this area.
Meanwhile, more than half want to see a fall in the number of asylum seekers coming to the UK, despite the fact they make up the smallest proportion of immigrants, just 4% in 2009.
And while almost two-thirds backed reducing immigration among low-skilled workers, which come mostly from the EU, only a third wanted to see fewer skilled migrants.
But international conventions and EU membership constrain the Government from reducing the numbers of asylum seekers or EU migrants in the UK, the report said.
Dr Scott Blinder, its lead author, said the survey exposed the difficulties the Government faces in meeting public demand.
"The Government is stuck between a rock and a hard place," he said.
"A clear majority of people in Britain would like immigration reduced, but they want the cuts to come from specific groups of immigrants, and these are often groups over whom the Government has limited direct control, and sometimes groups that are comparatively small in number."
He added: "Blunt questions about whether the British public supports or opposes immigration in general do not capture the complexities of many people's real views, and are not nearly fine-grained enough to give policy-makers a real understanding of what a majority of the public wants."
But Immigration Minister Damian Green said: "We have made sweeping changes to get a grip on immigration in this country, closing down routes that were subject to abuse and taking action against those with no right to be here.
"This is clearly in line with what the public want us to be doing. There is much more to be done and we will stick to our course."
:: Ipsos Mori carried out face-to-face interviews with 1,002 people aged 15+ in Britain between September 2 and 8.