British retail sales unexpectedly fell for a fifth month in a row last month, despite a rush of motorists filling up their cars with fuel, adding to signs Britain's economic recovery is losing momentum.

Sales volumes dropped by 0.2% in September, official figures showed today, bucking economists' expectations in a Reuters poll for a monthly rise of 0.5%.

However retail sales are still 4.2% higher than in February 2020 before Britain went into lockdown.

The five falls marked the longest period of consecutive monthly falls in the history of this series, which began in 1996.

The softness in recent spending will add to the conundrum faced by the Bank of England next month, as it decides whether to counter rapidly rising inflation by raising interest rates immediately or whether to wait for the economy to get on a firmer footing.

"Overall, the data support our view that the economic recovery stalled in September," said Bethany Beckett, UK economist at Capital Economics.

Weakness in retail sales in the third quarter will reduce overall third-quarter economic growth by 0.2 percentage points, the Office for National Statistics said, at a time when the broader economy has still not regained its pre-pandemic size.

British retail sales grew strongly in the first part of the year as lockdown restrictions were eased first for shops.

But they have fallen more recently, partly as people spent more on socialising after lockdown rules for pubs and restaurants were relaxed.

Sales are now 1.3% lower than a year earlier, weaker than the Reuters poll forecast for a 0.4% dip.

"Household goods were the main driver of this month's decline with a fall of nearly 10%, while food sales ticked back up after falling last month," ONS statistician Darren Morgan said.

Supply-chain bottlenecks have led to gaps on some supermarket shelves, and many petrol stations ran out of fuel in late September and early October after disruption to tanker deliveries led to queues of cars trying to fill up.

Petrol sales in September exceeded pre-pandemic levels for the first time, the ONS said.

Retail sales excluding fuel fell by a bigger-than-expected 0.6% on the month.

Looking at the third quarter as a whole, retail sales were down by 3.9%, their largest fall of any three-month period since the three months to March, when the economy was still largely under lockdown.

Consumer price inflation is also picking up sharply, due largely to higher energy prices, and the Bank of England predicts it will exceed 4% around the end of this year, double its target level.

A narrower measure of inflation used in the retail sales data rose to 3.7% in September, its highest since December 2011.

The prospect of higher prices - as well as a more recent upsurge in Covid-19 cases - has also dampened consumers' mood.

GfK reported earlier today that its long-running sentiment survey showed the lowest morale since February, when Britain was still in lockdown.