The United States in 1946 proposed to pay Denmark $100 million to buy Greenland after flirting with the idea of swapping oil-rich land in Alaska for strategic parts of the bleak Arctic island, documents in the National Archives show.

The $100 million was to be in gold. And even though the sale did not go through, the United States ended up with the military bases it wanted, anyway.Discovery of the documents, which have been declassified since the early 1970s, was first reported Sunday by the Copenhagen newspaper Jyllands-Posten.

One alternative that was discussed was for the United States to trade land in the Point Barrow district of Alaska for those portions of Greenland that the United States considered of military value.

Under this plan, the Danes would have received the rights to any oil discovered in the district and would have had to sell the oil to the United States.

The richest oil strike in U.S. history was made in 1967 in the Prudhoe Bay area, 200 miles east of Point Barrow. The Point Barrow area now is part of the National Petroleum Reserve, which are oil fields reserved for national defense.

The proposed purchase apparently first came up in November 1945, when Sen. Owen Brewster, R-Maine, said American military and naval authorities favored it and he considered it "a military necessity."

The U.S. Air Force currently maintains two bases in Greenland, Thule and Sondestrom.