There are 23 fewer jobs for British workers for every 100 migrants from outside the EU, the Government's immigration advisers said today.
An increase of 100 foreign-born working-age migrants in the UK was linked to a reduction of 23 Britons in employment between 1995 and 2010, the Migration Advisory Committee (Mac) said.
It comes after a report by the National Institute of Economic and Social Research (Niesr) said the number of immigrants coming to the UK had little or no impact on the number of unemployed.
Average wages remain the same, the Mac said, but it added: "Migrants are found to increase wages at the top of the UK wage distribution and to lower wages at the bottom of the distribution."
The impact and displacement of British workers also does not last forever, the Mac report found.
"Those migrants who have been in the UK for over five years are not associated with displacement of British-born workers," it said.
Between 1995 and 2010, the total working-age migrant employment rose by 2.1 million and currently displaces 160,000 British-born workers, it said.
But the report added that EU migration had "little or no impact on the native employment rate".
Professor David Metcalf, chairman of the Mac, said: "Assessing the impacts of migration is not a simple decision and our conclusions will require careful consideration by the Government.
"However, our research suggests that non-EEA migration is associated with some displacement of British workers.
"Financial impacts of migration are also complicated but considering overall GDP does not present a true picture.
"Instead, the impact of migration on the economic well-being of the resident population should be the focus."
He went on: "Impact assessments must also consider wider effects such as the effects of skills transfer from migrants and their impacts on public finances, employability of UK workers, housing and transport.
"Although difficult to measure, these will ensure we can better understand the effects of migration."