Wholesale inflation rose more than expected last month on a big jump in fuel costs as rising prices become a bigger economic challenge for millions of Americans, and a growing political problem for Republicans in the upcoming midterm elections.

The Labor Department's producer price index - which captures inflation before it reaches consumers - soared 6. 3% in September from a year ago, up from 5. 6% in August and the biggest increase since December 2022, the government said Thursday.

On a monthly basis, wholesale prices rose 1. 3% from August to September, marking the largest increase since March 2022, after a 0. 5% gain the previous month.