Britain’s economy grew more quickly than previously thought in the second quarter of this year though the start of 2014 was more sluggish, according to revised official figures.

They showed that gross domestic product (GDP) expanded by 0.9% from April to June, compared to a previous estimate of 0.8%.

However, the Office for National Statistics (ONS) data also calculated that first quarter growth was 0.7%, down from 0.8%.

It came as the ONS also revealed that the UK economic downturn ended around nine months earlier than first thought.

Methodological changes and data revisions meant GDP reached its pre-recession peak in the third quarter of 2013 rather than in the second quarter of this year.

It means the economy is now 2.7% larger than it was in the first quarter of 2008, the last period before the recession took hold.

The changes also mean that the economy is £27.8billion, or 6.6%, larger than had been earlier estimated, in current prices.

The latest revisions showed the economy was boosted by a much better performance from the construction sector in the second quarter than previously thought as well as a small improvement in the dominant services sector, which represents three-quarters of output.

Growth in the first quarter was revised down partly because household expenditure was lower than had been thought.

The new figures come after changes in methodology to include spending on research and development as well as illegal activities such as drugs and prostitution, in addition to the usual periodic revisions of ONS data.

It revealed earlier this month that the recession of 2008-09 had not been as deep as previously thought, with a “peak-to-trough” contraction of 6%, rather than 7.2% as previously thought. The subsequent recovery up to 2012 has also been quicker, the ONS said.

Today’s figures showed that GDP in 2013 grew by 1.7%, the same as previously thought. Meanwhile, separate balance of payments data published by the ONS showed the current account deficit widened to £23.1bn in the second quarter, up from £20.5bn in the first quarter.

The trade deficit - the gap between imports and exports - narrowed but UK firms investing abroad saw a £2.7bn plunge in profits from these overseas ventures.

James Knightley, of ING Bank, said the larger size of the economy suggested there was less wasteful “spare capacity” or underperformance in the UK than previously thought.

This key measure is one that Bank of England policy makers want to see narrowing before any increase in interest rates.

Mr Knightley said: “Taken on its own this could suggest that the UK may need to raise rates earlier and more aggressively than previously expected, but in the absence of inflation and wage pressures and with signs that the housing market is cooling we doubt that the Bank of England will move imminently. We still favour a February hike.”

But Samuel Tombs, of Capital Economics, said: “Today’s significant revisions to the UK’s national accounts do not change the fundamental picture that the economy’s performance since the recession began in 2008 has been very weak by historical and international standards.

“It remains the case that it took longer than after any of the recessions in the 20th century for output to return to its peak.”