The US economy is facing inflationary pressures following April's rise in consumer prices.

The nation's average retail prices of goods and services climbed a seasonally adjusted 0.6% last month, up from 0.4% in March, and rising at a 3.5% annual rate, according to the Labor Department. The monthly increase was led by a 3.9% jump in energy prices.

Economists, however, are more concerned by steeper-than-expected gains in the prices of services, such as rent, pushing up 'core' consumer prices.

Core prices in April were up 2.3% from a year earlier - near the top end of the Federal Reserve's 'comfort zone' - exceeding March's increase of 2.1%.

A sustained trend would make it difficult for new Fed chairman Ben Bernanke to establish inflation-fighting credentials without stifling economic expansion.

Data sourced from Wall Street Journal Online; additional content by WARC staff