An al-Qaeda leader Osama Bin Laden has sent another message, in which he blames global warming on the US and other big industrial nations. The audio tape also urges a boycott of the US dollar.
It comes days after another tape said to be from Bin Laden was released, praising the attempted bombing of a US airliner on 25 December.
The authenticity of neither tape has been verified.
But IntelCenter, a US group that monitors Islamist activity, has said the voice on the earlier tape appeared to be that of Bin Laden.
"All industrial nations, mainly the big ones, are responsible for the crisis of global warming," the latest tape says.
"This is a message to the whole world about those who are causing climate change, whether deliberately or not, and what we should do about that."
The tape criticises the administration of former US President George W Bush for not ratifying the Kyoto Protocol on combating climate change.
The tape also urges a boycott of the US dollar. "I know that there would be huge repercussions for that, but this would be the only way to free humankind from slavery... to America and its companies."
Responding to the earlier audio tape, also broadcast on al-Jazeera, US President Barack Obama said it indicated how weakened Osama Bin Laden had become.
"Bin Laden sending out a tape trying to take credit for a Nigerian student who engaged in a failed bombing attempt is an indication of how weakened he is, because this is not something necessarily directed by him," he said.
While the Yemen-based regional wing of al-Qaeda has said it was behind the attempted attack.
BBC News com. has contributed to the report.