The biggest baby boom in the UK for 40 years saw the country’s population grow more quickly than that of any other EU country last year, according to new official statistics.

The UK population reached 63.7m in mid-2012, according to annual estimates from the Office for National Statistics (ONS), an increase of just under 420,000, or 0.66 per cent, from a year before. This was a bigger absolute population rise than any other EU nation over the period, with France next at 319,000 and Germany seeing a 166,000 rise.

Of the population growth, 61 per cent was due to there being 254,400 more births than deaths over the period. The 813,200 births was the biggest number seen in the annual ONS figures since 1972.

The remaining 39 per cent of the increase came from net migration, with 517,800 overseas arrivals counted in these figures as people staying in the UK for at least 12 months and 352,100 departing.

The population increase was unevenly spread around the country, with Scotland and Wales seeing rises of 0.26 per cent and 0.34 per cent respectively, against 0.51 per cent for Northern Ireland and 0.73 per cent for England. London was the fastest-growing English region, seeing its population expand 1.27 per cent.

In mid-2012 England had an estimated total population of 53.5m, with 5.3m in Scotland, 3.1m in Wales and 1.8 m in Northern Ireland.

The population estimates, which the ONS describe as the “essential building blocks” for a series of other statistic models, show an increasingly ageing nation, with 10.8m people, or 17 per cent, aged 65 or over.