http://news.bbc.co.uk/1/hi/business/6083328.stm
Robert Plummer
"As in the US, where immigration has also become a hot political issue, experts seem to agree that the UK economy is bigger and faster-growing because of foreign-born workers. One study, by the accountancy firm Grant Thornton, concluded that as much as one percentage point of UK growth in 2005 and 2006 was contributed by migrants."