CHICAGO, Feb 27 (Reuters) - Spot basis bids for soybeans delivered by barge to the U.S. Gulf Coast were steady to higher on Thursday, while corn bids were mixed, traders said.

* Chicago Board of Trade corn Cv1 futures were down sharply on Thursday as market players digested numbers from the U.S. Department of Agriculture's Outlook Forum and expectations of new U.S. tariffs on imports from Mexico and China, analysts said.

* Uncertainty over the risk of tit-for-tat tariffs to disrupt U.S. agricultural exports continued to weigh over the market, traders said.

* U.S. President Donald Trump on Thursday said his proposed 25% tariffs on Mexican and Canadian goods will take effect March 4 along with an extra 10% duty on Chinese imports because deadly drugs are still pouring into the U.S. from those countries.

* Nearby empty barge freight is still fetching a premium, traders said, as barge fleets are seeing delays on the Mississippi River at St Louis due to loading and navigation back-ups, a broker said. BG/US

* CIF soybean barges loaded for split March traded at 87 cents over CBOT March futures SH25.

* CIF soybean barges loaded in February were bid at 88 cents over CBOT March futures SH25, steady from Wednesday, while March loadings were bid up 1 cent at 85 cents over futures.

* FOB export premiums for March soybean loadings were steady at 90 cents over futures.

* For corn, CIF barges loaded in March traded at 76 cents over CBOT March futures CH25, while barges loaded in April-May traded at 62 cents over May corn futures CK25.

* Meanwhile, CIF corn barges loaded in February were bid at 78 cents over CBOT March futures CH25, down 2 cents. March barges bid at 76 cents over futures, up 1 cent.

* Export premiums for corn loaded in the first half of March were 95 cents over futures, which was unchanged. Offers for the last half of March were 92 cents over futures, steady from Wednesday.

(Reporting by P.J. Huffstutter in Chicago; Editing by Rashmi Aich)

((pj.huffstutter@thomsonreuters.com; 313-484-5275 (w);))

For displays of CIF basis, click on the codes in brackets:
U.S. CIF Gulf soybeans GRYM
U.S. CIF Gulf corn GRYN
U.S. CIF Gulf SRW wheat GRYO
U.S. CIF Gulf HRW wheat GRYP
For displays of FOB basis, please click on the following codes in brackets:
U.S. FOB Gulf corn GRZC
U.S. FOB Gulf soybeans GRZD
U.S. FOB Gulf SRW wheat GRZE
U.S. FOB Gulf HRW wheat GRZF

LINKS Corn prices page:   cpurl://apps.cp./cms/?pageid=corn-cash-market
Wheat prices page:  cpurl://apps.cp./cms/?pageid=wheat-cash-market
U.S. barge freight                  BG/US
U.S. export sales estimates         USDA/EST
U.S. grain export summary           GRA/U
Brazil soybean export prices        SYBS
Brazil corn export prices           SYBX
Argentina grain prices              GRA/ARG
Russia grain prices                 GRA/RU