Falling US gas inventories also boosted natural gas futures traded in New York while export demand for wheat and soybeans lifted prices for those contracts in Chicago . Sugar rallied on hopes for higher use of the sweetener in the biofuel ethanol.

Oil prices were mixed, with US crude futures rallying on the weaker dollar and benchmark Brent oil in London slipping on the restart of a North Sea pipeline that would boost supply.

Copper and aluminium prices rebounded on the euro's rally against the dollar and better-than-expected US data that boosted the outlook for growth.

The dollar was down 1 percent against the euro by 2:45 p.m. ET (1845 GMT), on track for its sharpest slide in two months against the single European currency, after the European Central Bank left rates unchanged.

The greenback also fell against a basket of major currencies although it rallied versus the yen. A weak dollar tends to make commodities cheaper and more attractive to holders of other currencies.

The 19-commodity Thomson Reuters-Jefferies CRB index was up 0.8 percent, heading to its largest one-day gain in five weeks. Fourteen of the 19 markets tracked by the CRB showed gains.