Immigrants will swell Britain's population by a staggering 7.25m over the next fifty years, pre-budget documents reveal
Gordon Brown's predictions for future economic growth are based on migration adding 145,000 people to the population every year until 2055.
They will be responsible for three quarters of the total predicted rise of 9.7m in the number living in the UK.
The number living here in half-a-century's time will be an incredible 69.5m.
The level of net migration expected by the Treasury is slightly lower than the record levels currently pouring in.
Last year, net migration - the number of people arriving, compared to those leaving - was 185,000, or 500 a day.
But it is still a huge number, particularly as the Government has admitted having no idea how schools and hospitals have been coping with the recent influx.
It also dramatically outstrips the rate of net migration when Labour came to power in 1997 - then it stood at only 50,000.
The prediction also suggests the Chancellor plans to continue making use of cheap, overseas Labour to control wage inflation.
Critics have accused Mr Brown of taking a short-term approach. Instead of attempting to increase productivity, or lure jobless Britons off benefits and into work, he instead relies on large numbers of migrants to grow the economy.
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