US consumer inflation eased slightly last month, according to US government data published on Wednesday, a positive sign for President Joe Biden ahead of November's election.

The data supports the Biden administration's messaging that the US economy has turned a corner, as it looks to quell consumers' concerns about the impact of rising prices going into the likely rematch against former president Donald Trump.

The annual consumer price index (CPI) came in at 3.4 percent in April, down 0.1 percentage point from March, the US Labour Department said in a statement.

This was in line with the median forecast of economists surveyed by Dow Jones Newswires and The Wall Street Journal.

Monthly inflation came in at 0.3 percent, slightly below expectations.

The CPI data also helps the US Federal Reserve, which has hiked interest rates to their highest level for 23 years in a bid to bring inflation back down firmly to its long-term target of two percent.

It marks the first month of slowing annual data since January, although both the annual and monthly figures remain too high.

"The index for shelter rose in April, as did the index for gasoline," the Labour Department said in a statement.

"Combined, these two indexes contributed over seventy percent of the monthly increase in the index for all items," it added.

A widely-watched inflation measure excluding volatile food and energy prices also eased last month, rising at an annual rate of 3.6 percent, down from 3.8 percent in March.

The so-called "core" inflation index rose 0.3 percent in April from a month earlier, according to the Labour Department, also slightly lower than in March. (AFP)