A board at the TSX media centre shows the rate for the Canadian dollar against the greenback and the euro at 4:31 p.m. Wednesday. (Robin Rowland/CBC)

The Canadian dollar gained almost four cents Wednesday on global currency market, pushing the loonie close to 82 cents US.

The loonie was up 3.67 cents US at 81.63 cents at the close. It got as high as 82.45 earlier in the day.

The rise came as prices for oil and other commodities advanced and the U.S. dollar retreated.

In trading on the New York Mercantile Exchange, light sweet crude oil for December rose $4.77 to settle at $67.50 a barrel. The Canadian dollar is often said to be a "petro dollar," meaning it is closely tied to the rise and fall of the price of oil.

Other commodity prices, including copper, were also climbing on world markets.

In addition, the U.S. Federal Reserve sliced its key interest rate half-a-percentage point to one per cent - the lowest rate in four years - on Wednesday in yet another bid to loosen global credit markets and kick-start an increasingly moribund economy.

The U.S. dollar traded lower against the euro, the British pound, and the Japanese yen.