Energy Secretary Steven Chu said on Thursday high oil prices posed a threat to the global economy.
"The oil producer countries and the oil consuming countries are concerned because it does have an impact on a very fragile economic recovery. There is great concern," Chu told a news conference while attending a clean energy conference.
The conference was not attended by leading Gulf OPEC oil ministers. The UAE was represented by its environment minister.
Oil prices vaulted to their highest level since September 2008 this week, stoking concern among analysts and economists that the higher cost of fuel will crimp consumers' spending.
OPEC ministers, however, have said the organization cannot do anything to stop the rally as the market is already well supplied.
OPEC is not due to meet to discuss output policy until June, although Saudi Arabia has increased its own production to help compensate for the loss of Libyan oil exports amid fighting between rebels and forces loyal to leader Muammar Gaddafi.
Chu said he was aware that the Libyan rebels had been able to sell a cargo of crude oil but he did not have any details on the transaction.
"We know it has occurred. The United States is supportive of that sale and is supportive of the Libyan transitional government for that sale," he said.
Chu was in Abu Dhabi for the second Clean Energy conference along with ministers approximately two dozen other countries. Chu said the ministers made progress on international cooperation for the development of smart electricity grids, home appliance efficiency and electric vehicle deployment.
The countries participating in the forum account for about 80% of global greenhouse gas emissions and more than 70% of world economic output.
