A key gauge of inflation surged by much more than expected in April, confirming that the pace of inflation has accelerated.

The producer price index for final demand, which measures the prices paid to U.S. businesses for their goods and services, rose by 2.2 percent in April, the Department of Labor said Thursday. Compared with a year ago, the index is up 2.2 percent, the largest increase in a year.

The much hotter-than-expected inflation figure is likely to be seen as delaying any rate cuts from the Federal Reserve. Officials have said that they need to see evidence that inflation will continue to fall before they will begin reducing their federal funds benchmark interest rate.