The UK population is projected to become the largest in the EU
The UK population is set to become the largest in the European Union, according to a report.
It is expected to increase from its current figure of 61 million to almost 77 million in 2060 - a rise of 25%.
This would make it the largest population in the EU, ahead of the projections for France (72 million) and Germany (71 million).
The EU's statistical office Eurostat also predicts the EU population will be 506m in 2060, up from 495m in 2008.
It is expected to peak at 521m in 2035 but then decline.
The report predicts the average age of the EU population will rise, due to "persistently low fertility and an increasing number of survivors to higher ages".
The proportion of the population aged 65 or above in the UK is projected to reach 24.7% in 2060, from 16.1% in 2008.
The number of Britons aged 80 or above is expected to reach 9% in 2060, compared with the current figure of 4.5%.
If the projection is correct, 42.1% of the UK's population would be above retirement age - that proportion is currently 24.3%.
Ahead of the UK, the largest population growth within the EU is expected in Cyprus (+66%), the Irish Republic (+53%), Luxembourg (+52%).
A Home Office spokesman said: "Projections such as these are proof that we are right to be carrying out the biggest shake-up to the immigration system for a generation.
"Centre-stage is our new Australian-style points-based system, which means only those we need can come here to work or study."
Shadow home secretary Dominic Grieve said the figures showed it was "essential we develop a coherent strategy to deal with population growth".
He added: "This strategy must bring together policy on issues from the family to border control, housing to skills and planning to immigration control.
"We not only need to ensure that our population grows at a more sustainable rate but that we also prepare properly for that sustainable rate of growth.
"The government have shown that they have no answers to the challenges we face by failing to plan for our increasing population - this makes them part of the problem, not the solution."
Alasdair Murray, director of think tank CentreForum, said the projection should not be considered 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.
"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."