The Inuit Circumpolar Conference (ICC), representing native people in the vast, sparsely populated region girdling the Earth's far north, said on Wednesday in Montreal they had petitioned an inter-American panel to seek relief for Canadian and US Inuit.

"For Inuit, warming is likely to disrupt or even destroy their hunting and food-sharing culture as reduced sea ice causes the animals on which they depend to decline, become less accessible, and possibly become extinct," said Robert Corell who spearheaded an Arctic climate impact assessment.

Scientists say there is mounting evidence that the first effects of climate change are already kicking in, with the melting of Alpine and Himalayan glaciers and erosion of Arctic and Antarctic ice sheets.

They also speculate that this year's unprecedented season of Atlantic storms, spearheaded by Hurricane Katrina which devastated New Orleans, was caused by global warming.

Limits urged

Environmental activists marching in Montreal on the summit's eve

The Inuit petition urges the Washington-based Inter-American Commission on Human Rights to declare the US to be in violation of the 1948 American Declaration of the Rights and Duties of Man.

It also wants the commission to recommend that the US adopt mandatory limits of its greenhouse-gas emission and join international efforts to curb global warming.

And it wants the commission to declare the US should help the Inuit adapt to unavoidable impacts of climate change.

More than 150,000 Inuit, formerly called eskimos, are spread throughout the vast frozen northern territories of Alaska, Canada, Greenland, Scandinavia and Russia.

These regions have experienced the most rapid and severe climate change on earth, according to Corell's assessment, which was prepared over four years by more than 300 scientists from 15 countries and six indigenous organisations.

In Montreal, environment ministers from around the world heard on Wednesday a grim warning about the threat to the Arctic as they began three days of talks to climax a key conference on climate change.

Canadian view

Canadian Prime Minister Paul Martin, whose country is hosting the 12-day conference, said his nation's far north had become "an incubator for the altered world of tomorrow".

The conference gathers ministers or their stand-ins from 189 countries and entities under the UN Framework Convention on Climate Change (UNFCCC), the fruit of the 1992 Rio Summit.

The meeting's big focus is the future of the Kyoto Protocol, the troubled UN pact on curbing greenhouse gases.

In his speech, Martin said: "High in the Arctic, in our interior and along our coasts, the country we know is being transformed," he said.

"Winters are growing milder, summers hotter and more severe, there is plant life where before there was none; there is water before there was ice. Our permafrost is thawing, and releasing methane gas into the atmosphere."

He added: "Within short decades, the Northwest passage, the famously unnavigable thoroughfare of history, may be passable - a striking and unsettling example of our delicate balance succumbing to untenable strain."

Past time

Martin blasted the small but influential minority of sceptics who doubted that Man had interfered with Earth's delicate climate balance.

"The time is past to debate the impact of climate change. We no longer need to ask people to imagine its effects, for now we can see them."

Martin made a veiled attack on the Bush administration's position warning that no one was immune from climate change.

"The time is past to seek comfort in denial. The time is past to pretend that any nation can stand alone, isolated from the global community ... there can be no hiding on any island, in any city, within any country, no matter how prosperous, from the consequences of inaction."