Greenland is an autonomous territory under Danish sovereignty, but the cables show that US diplomats believe it "is on a clear track to independence," which they also see as "a unique opportunity" for American gas and oil companies.
A Greenlandic official is quoted describing his "country" as "just one big oil strike away" from independence.
The Arctic is estimated to hold about a quarter of the world's undiscovered oil and gas reserves.
In another cable, the then-US Ambassador to Denmark, James P. Cain, says that he has introduced "some of our top US financial institutions" to two of Greenland's governmental ministers "to help the Greenlanders secure the investments needed for such exploitation".
At one point, Danish Foreign Minister Per Stig Moeller jokes with the Americans that "if you stay out, then the rest of us will have more to carve up in the Arctic".
The cables have leaked as Hilary Clinton became the first US Secretary of State to attend an Arctic Council meeting today, signalling the region's rising importance in Washington.
"This is an important innovation in the architecture of regional and global cooperation," Deputy Secretary of State James Steinberg said of the Council earlier this week.
Due to rising temperatures, summer ice around the Arctic may soon disappear, devastating the livelihoods of indigenous peoples and threatening polar bears and other polar mammals.
But it could also increase access for shipping, mining and oil and gas exploration and countries including Canada, Denmark, Norway and Russia have already staked claims in the region.
Last week, a new international study projected that an accelerated melt of Arctic ice would cause world sea levels to rise by three to five feet by 2100, more than previously projected.
That sparked calls by Nordic nations for more action to slow climate change and more focus on the Arctic in sluggish UN negotiations on a global deal.
Today's conference - the seventh annual meet - is expected to formally agree a deal dividing search-and-rescue responsibility among Arctic states.
Moves to coordinate oil and gas development in the region may also be considered, along with the establishment of a permanent council secretariat to help strengthen the organisation's governance role.
The Arctic Council includes Canada, Denmark (which handles foreign affairs for Greenland), Finland, Iceland, Norway, Russia, and Sweden, as well as groups representing the region's indigenous inhabitants.
It is an international organisation formed to promote cooperation among the nations making up the Arctic region, which covers more than a sixth of Earth's landmass.
(EurActiv with Reuters.)