U.S. consumer prices increased more than expected in October as the cost of gasoline and food surged, leading to the biggest annual gain since 1990, further signs that inflation could remain uncomfortably high well into next year amid snarled global supply chains.

The U.S. consumer price index (CPI) rose 0.9 percent last month after gaining 0.4 percent in September, the Labor Department said on Wednesday.

In the 12 months through October, the CPI accelerated 6.2 percent, which was the largest year-on-year advance since November 1990 and followed a 5.4 percent jump in September.

Excluding the volatile food and energy components, the CPI gained 0.6 percent after climbing 0.2 percent in September. The so-called core CPI jumped 4.6 percent on a year-on-year basis, the largest increase since August 1991, after being steady at 4 percent for two straight months. Economists polled by Reuters had forecast the overall CPI shooting up 0.6 percent and the core CPI rising 0.4 percent.

Inflation is heating up again as the economic drag from the summer wave of COVID-19 infections, driven by the Delta variant, fades and supply bottlenecks persist. Trillions of dollars in pandemic relief from governments across the globe fueled demand for goods, leaving supply chains overstretched.

The nearly two-year-long pandemic has upended labor markets, causing a global shortage of workers needed to produce raw materials and move goods from factories to consumers. The government reported on Tuesday that producer prices increased strongly in October, reversing a slowing trend in the monthly producer price index (PPI) that had become entrenched since spring.

(With input from Reuters)