The Organization of Petroleum Exporting Countries in its May report said it expected the U.S. economy to experience gains this year. OPEC said there was recovery under way in the labor market and the housing sector that was helping the U.S. economy.
It said budget cuts under the so-called sequester and general uncertainty about congressional budget negotiations deserved close attention as possible setbacks for the United States, however.
For the eurozone, OPEC said leading indicators point to ongoing retractions in industrial production and unemployment. The prospect for a second quarter recovery "remains to be seen," the cartel said.
Growth in the Chinese gross domestic product slowed to 7.8 percent last year. Last month, OPEC said it expected GDP growth of 8.1 percent but revised that to 8.0 percent because of weak demand for Chinese exports.
OPEC said world GDP growth expectations haven't changed, however. Oil demand forecasts from emerging and developed countries have offset problems in Europe and elsewhere.
"The latter half of the year will see much higher oil use, reaching 90.1 million bpd and 90.9 million bpd in the third and fourth quarters, respectively," the May report said.