British consumer price inflation surged to its highest in more than 10 years in November, jumping to 5.1% from October's 4.2%, in news likely to unsettle the Bank of England as it considers whether to raise interest rates on Thursday.
Price pressure from a broad range of goods and services - but especially petrol, clothing and footwear - were responsible for the rise, the Office for National Statistics said.
The reading exceeded all forecasts in a Reuters poll of economists, which had pointed to a rise of 4.7%.
Sterling briefly jumped on the news, but at 0735 GMT it was little changed compared with its level before the data. Short sterling interest rate futures priced in slightly higher rates for 2022 and 2023 but no change for December.
"Despite today's inflation figures, we expect the Bank of England to adopt a wait-and-see approach at this week's meeting, allowing for more time to assess the net impact of the Omicron variant on growth and inflation," KPMG economist Yael Selfin said.
The International Monetary Fund predicted on Tuesday that British inflation would reach around 5.5% in the second quarter of next year - its highest in 30 years - and warned the Bank of England not to succumb to "inaction bias".
Globally, inflation has risen much faster than economists expected this year, due to higher energy prices and COVID-related supply-chain bottlenecks. In Britain, post-Brexit trade and migration barriers have also caused problems.
The BoE has said interest rates will almost certainly need to rise to bring down inflation, but held off on a widely expected move last month due to uncertainty about the impact of the end of the government's job furlough programme.
Most economists had not expected the BoE to raise interest rates on Thursday after its December meeting, because of the unknown scale of the threat posed by rapidly rising cases of the Omicron coronavirus variant.
Wednesday's data showed core CPI, which excludes more volatile energy, food, alcohol and tobacco prices, rose to 4.0% from October's 3.4%, above all economists' forecasts and the highest since 1992.
The long-running retail price inflation (RPI) measure - which the ONS says is no longer accurate, but which is still used for inflation-linked government bonds and wage-bargaining - rose to 7.1% from 6.0%, its highest since March 1991.