British retail sales recorded their strongest monthly growth in almost two years last month, boosted by bumper beer sales linked to the Rugby World Cup hosted in England and Wales. 

Retail sales volumes surged by 1.9% on the month, far higher than economists' forecasts for a 0.3% rise, the Office for National Statistics said.

The figures marked a break with disappointing data in the previous two months. 

For the third quarter as a whole, retail sales rose by 0.9%, up from 0.8% growth in the second quarter, and offering some hope that consumer spending supported Britain's economy as a whole over a period when export demand faltered. 

"Falling in-store prices and promotions around the Rugby World Cup are likely to be the main factors why the quantity bought in the retail sector increased in September at the fastest monthly rate seen since December 2013," the ONS said. 

UK retail sales alone were likely to boost third-quarter GDP by 0.1%, the ONS added. 

For the 12 months to September, retail sales were up by 6.5%, their biggest increase since November 2014 and well ahead of economists' forecasts of a 4.8% rise. 

The strong growth in sales volumes was supported by falling prices, with the measure of inflation used in the data showing store prices were down by 3.6% on the year, the joint-biggest fall since the series began in 1988. 

Food and drink sales rose by 2.3% on the month, the biggest rise since April 2014. But the boost to spending from the four-yearly Rugby World Cup may fade in October, after England's early exit from the tournament. 

Most economists had expected the ONS data to show some bounce back in retail sales in September, after private-sector surveys by the British Retail Consortium and the Confederation of British Industry had shown a recovery in spending. 

The ONS said the value of retail spending was up 2.7% on the year, compared with a 3.9% rise in spending recorded by the BRC in September.