Copper prices retreated Wednesday on concern stimulus measures by central banks from the U.S. to Japan may fail to bolster economic growth and demand for metals.

New bond purchases announced this month by the U.S. central bank probably won’t boost growth or hiring, Federal Reserve Bank of Philadelphia President Charles Plosser said Tuesday. Copper is on course for the biggest monthly gain since January after the European Central Bank said it would buy indebted nations’ bonds and the Bank of Japan enlarged an asset-purchase fund.

The market “is still in consolidation mode after the euphoria over the last few weeks,” Robin Bhar, an analyst at Societe Generale SA in London, said by phone.

Copper for delivery in three months declined 1 percent to $8,193 a metric ton by 10:49 a.m. on the London Metal Exchange, reducing this month’s advance to 7.6 percent. Copper for December delivery fell 0.7 percent to $3.732 a pound on the Comex in New York.

Prices also retreated as the dollar advanced for a third day against the euro, reducing the appeal of raw materials as an alternative investment. German Chancellor Angela Merkel met Tuesday with ECB President Mario Draghi and was to speak Wednesday with International Monetary Fund chief Christine Lagarde as officials grapple with the euro-region debt crisis.

“The news out of Europe is a bit more negative, with lots of meetings taking place,” Bhar said. “The euro is weakening. That’s just adding a bit of caution into the market.”

The biggest manufacturers in Japan, which ranks fourth globally among copper consumers, grew more pessimistic this quarter as China’s slowdown and Europe’s debt crisis sapped exports, according to a Bloomberg survey. The BOJ will say Oct. 1 business confidence in its Tankan survey fell to -4, the fourth quarter pessimists outnumbered optimists, it showed.

Copper stockpiles monitored by the LME rose for a third day to 220,525 tons, daily exchange figures showed. Orders to withdraw metal from warehouses slid 2.5 percent to 39,425 tons.

Aluminum, tin, zinc, nickel and lead fell in London.