Britain is set to become the most populated European Union nation within 50 years because of high immigration and birth rates, research has revealed.

A report published by the European Commission predicts that by 2060, Britain's population will have risen from today's figure of 61.2 million to 76.6 million, making it the most crowded nation of the European Union's 27 member states.

Immigration and birth rates are the main contributory factors to the changes predicted for the UK.

The numbers are almost equal - 7.7 million people are forecast to have migrated to the country by 2060, while a further increase of 7.69 million as a result of births and deaths will raise the population total by 15.4 million.

But Alasdair Murray, director of think tank CentreForum, said that the figures must be taken as a prediction and not as a certainty.

He said: "Population statistics are predicted by using recent figures so this report will have used the statistics of immigration in the UK in the last few years. The level is high so the prediction will be high."

He added: "There are signs that immigration in this country is starting to tail off, if you were to do this again in 2010 or 2011 I think it would be different.

"A more realistic assessment would be to consider the two factors of birth rates and immigration rates together when predicting population."

Germany is predicted to have the biggest population drop, down 11.4 million to a total of 70.7 million, with a fall in birth rates cited as the main factor.

Figures also show that the total population of the EU will rise from 495.4 million in 2008 to 520.7 million in 2035, and will slowly decline to 505.7 million by early 2060.

It is also expected to be made up of older people.

People aged 65 years or over are predicted to increase from 84.6 million to 151.5 million and those aged 80 years or over is projected to almost triple from 21.8 million to 61.4 million in 2060.

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