The conservation charity WWF and an ad agency have admitted that a press campaign comparing the loss of life in the New York 9/11 attacks and the Asian tsunami "should never have been made".

The Brazilian press ad, created by local advertising agency DDB Brasil, is called "Tsunami" and uses images of dozens of planes about to crash into New York City skyscrapers to illustrate the scale of the lives lost in the 2004 Asian tsunami.

WWF's ad, which also shows the World Trade Center towers destroyed in the terrorist attacks of 2001, was created and approved at the end of last year and appeared briefly in the Brazilian press.

In a joint statement yesterday from WWF Brazil and DDB Brasil, posted on the ad agency's website, they admitted that the press ad was "created and approved" for use.

"It was created and approved in late 2008, mistakenly, and was solely the result of lack of experience on the part of a few professionals from both parties involved," the joint statement said.

"In no way was it done in bad faith or with disrespect to American suffering. WWF Brazil and DDB Brasil acknowledge that such an ad should never have been made, approved or published."

This followed an earlier statement from WWF Brazil admitting that the 9/11 press ad concept had been presented as a campaign idea by DDB Brasil in December – but denying that it had been approved to run anywhere.

Earlier yesterday, WWF had also put out a statement from its US office initially claiming it was being "inaccurately" linked to the press ad, before the admission of responsibility from the organisation's Brazilian arm.

The press ad was also submitted to an awards show in the US. What purports to be a video version of the ad has subsequently appeared online, featuring a recreation of the New York skyline, including the World Trade Center. However, both the WWF and DDB Brasil deny any involvement in the creation of the video.

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