Wheat climbed to a two-week high, while corn was little changed after rising 1.5 percent in the last session.

The most-active soybean contract on the Chicago Board Of Trade rose 0.3 percent to $9.95 a bushel by 0334 GMT, the highest since Dec. 8. Soybeans last rose for at least nine straight sessions in March 2012.

Wheat added 0.4 percent to $4.34-3/4 a bushel, having closed up 2.7 percent on Wednesday, while corn was unchanged at $3.56-1/2 a bushel.

"We have seen a big run-up in soybean prices as there have been weather concerns in Argentina," said Phin Ziebell, agribusiness economist at National Australia Bank.

"But the rally could be running out of steam as there is no major supply risk with ample supplies in the United States and Brazil."

Soybeans were supported by concerns about drought in parts of Argentina, the world's third-largest soybean producer and largest exporter of soymeal and soyoil.

Dryness there has fuelled forecasts of lost plantings and yield damage that could potentially tighten global supplies and make US exports look more attractive.

Still, the United States has ample supplies from last year's bumper harvest, while Brazil is on track for another record crop.

Grains complex had been underpinned by a weaker dollar, increasing the competitiveness of US supplies.

The dollar skidded to a three-year-low against its peers on Thursday after caving on comments by US Treasury secretary Steven Mnuchin that he welcomed a weaker currency, while the euro was firm ahead of the European Central Bank's policy decision.

Commodity funds were net buyers of Chicago Board of Trade corn, wheat and soybean futures contracts on Wednesday, traders said.