The Conservatives accused Prime Minister Gordon Brown of being in denial about the UK Government’s record on immigration last night.
Shadow home secretary David Davis made the attack after the prime minister insisted British business had benefited “very substantially” from immigration over the last decade.
Mr Brown said that gross domestic product per head had risen dramatically since 1997, from £13,900 then to £22,840 in the last year.
He appeared to reject a suggestion by an influential House of Lords committee that immigration levels should be capped, noting that such a move could apply only to those coming from outside the EU.
“Most people who are proposing a cap are proposing a cap of only 20% of possible migrants into this country,” Mr Brown said.
“And of course many of these people are the highly-skilled workers who are important to the economy.
“Most people in the City of London know they have benefited very substantially.”
He told his monthly Downing Street press conference that the government had introduced a points-based immigration system so that there would be no unskilled immigrants from outside the European Union.
And the government had addressed strains on services in certain areas with additional financial support.
But Mr Davis said of Mr Brown’s 20% figure: “The prime minister is in denial.
“His minister’s previous assertions about this have been shown to be bogus.
“It’s either a sign of desperation or pure lack of grasp that he is repeating them.”
Tory leader David Cameron said: “We want people to work here and come to Britain. The problem with the government is that they absolutely refuse to set any sort of limit on immigration.”
He added: “If you want to control immigration you have to control that bit of immigration you are able to control. It’s still possible to control non-EU immigration.”
The peers’ report dismissed the government’s claim that immigration is good for the economy and called on ministers to set an “explicit target range” for the number of arrivals.
The report concluded that record immigration had led to “little or no impact” on economic wellbeing.
The CBI’s head of employment, Neil Carberry, responded: “In the global economy, businesses need a flexible immigration system that allows them to source the skills they need when appropriate UK-born staff cannot be found.
“But employers have never argued for uncontrolled, mass migration and large-scale movement of labour is no long-term answer to our skills’ needs.”
Chris Hannant, of the British Chambers of Commerce, criticised aspects of the report.
“The value of migration to our member businesses and the economy as a whole has been substantial,” he said.
“By focusing on GDP the report ignores the contribution made by migrant labour in plugging the skills gaps that blight our economy.
“Without the steady flow of migrant labour into the UK most businesses would be struggling to expand or fill vacancies.”