Bin Laden struggling to stay relevant: US

The United States said Friday that Osama bin Laden was struggling to stay relevant after the fugitive Al-Qaeda chief released an uncharacteristic tape addressing issues like climate change.

"So we've gone from being the 'Great Satan' to the 'Great Emitter,'" State Department spokesman Philip Crowley said sarcastically.

"He's working hard to stay relevant -- that's all I can say."

In the message aired on Al-Jazeera television, possibly timed to coincide with the World Economic Forum in Davos, bin Laden said "all industrial nations, mainly the big ones, are responsible for the crisis of global warming."

He also urged a boycott of the US dollar, saying it would be "the only way to free humankind from slavery... to America and its companies."