Consumer inflation held steady in the United States last month, according to government data released on Thursday, giving policymakers some reprieve in their battle to tamp down price increases.

The consumer price index (CPI), a closely watched inflation gauge, rose 3.7 percent from a year ago, the same rate as in August, the Labour Department said.

But on a month-to-month basis, inflation slowed from 0.6 percent to 0.4 percent, according to the latest report.

In addition, underlying gains were muted. The index with volatile food and energy segments stripped out cooled to 4.1 percent – the lowest in two years.

The numbers could bring some relief to President Joe Biden, who has been struggling to combat gloomy sentiment on his handling of the economy as he campaigns for reelection.

"Overall inflation is down by 60 percent from its peak," Biden said in a statement on Thursday, adding that unemployment has remained relatively low in recent months.

"That's Bidenomics in action," he added, referring to his economic agenda.

Slowing inflation will also be good news for the Federal Reserve, which has waged an aggressive campaign of interest rate hikes since March last year to lower demand and in turn, the pace of rising costs.

Although Fed policymakers have left the door open to another rise in the benchmark lending rate this year, lower inflation figures could reduce the need for one when their next meeting wraps up in November.

The Labour Department said that apart from shelter costs, an increase in petrol prices was a "major contributor" to the September figure.

"While the major energy component indexes were mixed in September, the energy index rose 1.5 percent over the month," the department noted. (AFP)