Copper closed at the highest in almost eight weeks as a slumping dollar made the metal cheaper for buyers using other currencies.

ICE Futures U.S.'s dollar index, which measures the U.S. currency against the weighted values of the euro, yen, pound, Canadian dollar, Swedish krona and Swiss franc, fell to a 15- year low.

The metal last week surged 5.9 percent after the Federal Reserve cut its benchmark interest rate to bolster U.S. economic growth in the face of a housing recession.

Copper futures for December delivery gained 5.25 cents, or 1.5 percent, to $3.645 a pound on the Comex division of the New York Mercantile Exchange, the highest closing price for a most- active contract since July 31.

Copper has gained 27 percent this year, while the dollar dropped 6.7 percent against the euro. The metal, used in homes, cars and appliances, sometimes moves in tandem with economic expansion.