* Wheat rises for 4th session, at highest since Dec. 2012

* Soybeans firm, concerns over demand limit gains; corn unmoved

SINGAPORE, Nov 24 (Reuters) - Chicago wheat rose on Wednesday for a fourth consecutive session to scale its highest level since December 2012 as concerns about global supplies underpinned the market.

Soybeans gained ground after closing lower although worries about world demand kept a lid on prices.

"We don't see a downside for wheat prices as we are still waiting to see what happens to the Northern Hemisphere harvest," said Phin Ziebell, agribusiness economist at National Australia Bank.

"Global wheat stocks are low and protein levels are a concern."

The most-active wheat contract on the Chicago Board Of Trade (CBOT) was up 0.1% at $8.68-3/4 a bushel, as of 0244 GMT, near the session high of $8.71 a bushel, the highest since December 2012.

Soybeans were up 0.3% at $12.77 a bushel and corn added a quarter of a cent to $5.88-1/2 a bushel.

Concerns about tightening global supplies have supported wheat prices, as rains stalled harvesting in Australia and threatened grain quality. Flooding has also disrupted shipments from western Canada, while prices in Russia, the world's top wheat exporter, have climbed steadily.

Early harvest results for Australia's near record wheat crop are showing lower-than-expected protein levels, raising concerns over supplies to a market already suffering shortfalls from key Northern Hemisphere exporters.

Dry conditions in the U.S. winter wheat belt also fuelled early worries about next year's harvest.

The U.S. Department of Agriculture (USDA) said on Monday that 44% of the U.S. winter wheat crop was in good-to-excellent condition, down from 46% a week earlier. Analysts on average had expected an unchanged score.

The agency cut on Tuesday its U.S. farm exports forecast for next year, citing weaker soybean demand from China and lower bean prices.

Commodity funds were net buyers of CBOT wheat, corn and soyoil futures contracts on Tuesday and net sellers of CBOT soybeans and soymeal, traders said. (Reporting by Naveen Thukral; Editing by Sherry Jacob-Phillips)