Wed Jun 23, 9:32 AM ET

An oil stained pelican sits on a dredging hose in Barataria Bay June 19 near Port Sulpher, Louisiana. The International Energy Agency says the BP oil spill in the Gulf of Mexico is a catastrophe caused by human error which could have been avoided.

PARIS (AFP) – The oil spill in the Gulf of Mexico is a catastrophe caused by human error which could have been avoided, the head of the International Energy Agency said here on Wednesday.

"This is a catastrophe that could have been avoided," IEA director general Nobuo Tanaka told a press conference on the occasion of publication of the agency's medium-term outlook for the oil market..

He said: "We have to wait until the investigation."

But from the information available, "there is an accumulation of human errors."

While awaiting the results of an enquiry into the accident, the moratorium on deepwater drilling decided by the US administration, "is a reasonable measure," he said.

On Tuesday, a judge in Louisiana annulled the six-month moratorium.

Referring to the effect of the spill on the oil market, Tanaka said that it had "so far has been minimum."

But he also said that the impact on new deepwater projects could reduce expected US oil output in the Mexican gulf by 100,000 to 300,000 barrels per day.

Similar restrictions worldwide, although very unlikely, "could ramp the number up to 800,000 to 900,000 bpd."

The International Energy Agency is the oil policy arm of the 31-member Organisation for Economic Cooperation and Development.