The number of migrant workers who have come to Britain from new EU member states since last May is far higher than previously thought, according to new figures.
Almost 91,000 people from the eight states that joined the EU in May have registered to work in the UK during the past five months, with Poland accounting for 48,500 of the applicants.
The government had previously said that it estimated between 5,000 and 13,000 people from the accession states would come to the UK annually to seek work.
The Home Office figures show that 96 per cent of these registered workers are working fulltime, paying an estimated £20 million in tax and national insurance and contributing £120 million to Britain's GDP.
But according to shadow home secretary David Davis: “The TUC reported that not all workers are registering and coupled with official statistics showing that between May and August 542,000 visited the UK, an increase of 222,000 from last year, and without embarkation controls, there are probably many more people working illegally."
While politicians argued over the implications of the figures, business leaders pointed out that migrant labour was desperately needed to fill the 600,000 vacancies in Britain, many of them low-paid roles in agriculture and hospitality that are difficult to fill.
The Chartered Institute of Personnel and Development (CIPD) said that pressure to limit migration should be resisted because it would damage the economy.
CIPD chief economist Dr John Philpott said: “Any further arbitrary tightening of the rules governing immigration could risk damaging business prosperity and government efforts to improve public services.
Underlining Philpott's argument, the latest figures also show that four out of ten migrant workers are now employed in rural communities, a big shift from 2001, when almost half of all foreign nationals working in Britain were in London.
And a report published earlier this week by the TUC found that migrant workers are effectively propping up the rural economy in areas such as East Anglia where Eastern European migrants are filling many key positions in agriculture, hospitality and food processing.
"Far from sponging as some claimed, workers from the new Europe are propping up the local economy in large parts of rural and small town Britain," TUC general secretary Brendan Barber said.
Meanwhile Bob Cotton, chief executive of the British Hospitality Association, told the Times newspaper that many employers in hospitality were actively targeting staff from Poland, Hungary and Lithuania because British workers were reluctant to accept low-paid jobs.
"One of the biggest problems is that while we have a low level of unemployment, we have millions of people claiming benefits," he said.
"Some of these people would rather work fewer hours so they retain their benefits. Foreign workers are happy to work between 30 and 50 hours a week."