The UK population grew by almost half a million last year to 64,596,800, according to figures from the Office for National Statistics.

The "above average" increase of 491,100 from mid-2013 to mid-2014 included net migration adding 259,700 to population growth, the ONS figures show according to the BBC on Thursday.

This was more than "natural growth" - births minus deaths - which added 226,200.

The ONS said a quarter of births were to mothers born outside the UK.

The overall number of births was down compared with the previous year, continuing a downward trend seen since a peak in mid-2012.

The population increase was above average compared with rises over the last decade, the ONS said.

As well as net migration and natural growth, other changes and adjustments, mainly in the armed forces, accounted for an increase of 5,200 people, the ONS said.

The ONS figures show the annual growth in population rose steadily from about 150,000 in 1992 to about 300,000 in 2004, but that rose sharply in 2005 to 460,000.

It has remained above 400,000 since - 2014's net increase is the fifth biggest.

The figures found that the population of Scotland increased by 19,900 (up 0.37%) to 5,347,600 and accounts for 8% of the UK's population.

Meanwhile Wales' population increased by 9,600 (up 0.31%) to 3,092,000 and accounts for 5% of the UK's population

Northern Ireland's population, which accounts for 3% of the UK's population, increased by 10,800 (up 0.59%) to 1,840,500 people/

The lowest regional population increases in the year were seen in Wales, North East of England and Scotland growing by 0.31%, 0.32% and 0.37% respectively.

No country of the UK or region of England experienced a population decrease.