A sharp rise in energy costs pushed US consumer prices up at their fastest pace in nearly a year last month, but underlying price pressures remained muted, a government report showed on Friday.
The consumer price index, the most widely used gauge of US inflation, climbed 0.5 percent in January after a 0.2 percent rise the month before, the Labour Department said.
The so-called core CPI, which strips out volatile food and energy prices, gained just 0.2 percent.
Wall Street economists had expected the overall CPI to rise 0.3 percent and the core index to tick up a mild 0.1 percent.
The higher-than-expected readings pushed US Treasury bond prices down a bit and the dollar higher.
But the mild increase in core inflation held the 12-month change steady at the nearly 38-year low of 1.1 percent hit in December.
Economists said the benign reading on core inflation meant the Federal Reserve still could bide its time as it mulled when it should push overnight interest rates up from their 1958 low of 1 percent.
FUELING INFLATION: Much of the increase in consumer prices in January was due to a big jump in energy costs, which were up 4.7 percent last month - the biggest increase since March. Economists by and large had expected a big energy price gain.
Gasoline prices rose 8.1 percent, the largest jump since last February, while fuel oil spiked 7.2 percent and natural gas prices increased 3.8 percent.
The energy price increases were reflected in a sharp 1.7 percent increase in transportation costs, despite a drop in new car prices, and a 0.4 percent gain for housing.
Food prices were unchanged in January, while apparel costs slid for the third straight month.