Predictions that Britain’s population would be 70 million within 20 years are underestimates, a new projection from the Office for National Statistics has said. Instead, the population is likely to be 74 million within that time period.

The ONS figures have factored in current Third World immigration rates, which it says will boost Britain’s population by 12 million well within the next two decades.

According to its calculations of the “highest likely scale of future population growth,” Britain’s population will reach the 70 million mark in 2023, six years earlier than  predicted.

The ONS said its new estimates are based on immigration continuing at current levels and birth rates among new migrants. It said Britain’s present population, estimated to be just under 62 million, will rise at a rate of more than half a million every year, reaching 70 million in 2023 and 73.8 million by 2029.

Projected even further, this means that the 100 million mark will be reached by 2071.

Migrationwatch chairman Sir Andrew Green said that the “projections show

that the population will climb far into the future unless very tough measures are taken to cut back the massive levels of immigration that Labour has permitted, even encouraged.”

According to calculations made by Migrationwatch, foreign immigrants are now arriving at the rate of about 500,000 every year. This translates to nearly one a minute.

A new home must be built every six minutes for new migrants — in a country which is already the most crowded in Europe.

To keep the population of the UK below 70 million, immigration must be reduced by 75 percent. The new “points system” introduced by the Government might, if properly enforced, reduce immigration by five percent.

Currently, one British passport is handed out to an immigrant to this country every two minutes. During the first three months of 2009, 54,615 citizenship applications were approved by the Home Office  – one every two minutes.

At this rate, some 220,000 will have been issued before the end of the year. Last year, some 129,310 British passports were handed out in this manner.