Sept. 1 (Bloomberg) –Copper climbed to the highest in more than three weeks after data on U.S. factory orders and business activity bolstered confidence in the economy.

Orders placed with U.S. factories rose in July by the most in four months, Commerce Department figures showed today in Washington. Business activity expanded in August at a faster pace than forecast, according to the Institute for Supply Management-Chicago Inc. The U.S. is the world's second-biggest user of copper, after China.

"It looks like all the worst is behind us," Michael Smith, the president of T&K Futures and Options in Port St. Lucie, Florida, said today in a telephone interview. "Copper has made a bottom, and it will be upside from here."

Copper futures for December delivery rose 6.3 cents, or 1.5 percent, to close at $4.2045 a pound at 1:27 p.m. on the Comex in New York. Earlier, the price reached $4.223, the highest for a most-active contract since Aug. 5.

The metal dropped 6.1 percent this month --and 5.5 percent for the year -- touching an eight-month low of $3.818 on Aug. 9, on concern that the global economic recovery is faltering.

"The market's attention is refocused back on fundamentals, which for copper are supportive for higher prices," Gayle Berry, an analyst at Barclays Capital in London, said in a telephone interview.

Output in Chile, the biggest producer, slumped 18 percent in July from a year earlier, a report showed yesterday. Production was curbed by a two-week strike at the country's Escondida mine, the world's largest.

On the London Metal Exchange, copper for three-month delivery rose $115, or 1.3 percent, to $9,275 a metric ton ($4.21 a pound).

Aluminum, lead, zinc, nickel and tin also gained in London.