* Grains complex rebounds after stepping back on news of new coronavirus strain * Soybeans reach new highs on South American dryness, worker strikes (Updates closing prices) CHICAGO, Dec 21 (Reuters) - U.S. soybeans climbed to six-year highs on Monday as weather and export troubles in Argentina outweighed concerns of a new coronavirus strain hitting Britain. Corn and wheat futures traded near even as soybeans supported the grains complex. Chicago Board of Trade most-active soybeans gained 23-1/2 cents to $12.47-1/2 per bushel, after reaching $12.48-3/4 per bushel, their highest since June 27, 2014. Wheat added 3 cents to $6.11-1/4 per bushel, while corn gained 2-1/2 cents to $4.40 per bushel, after reaching $4.40-3/4 per bushel, its highest level since July 18, 2019. More than 100 cargo ships were kept from loading agricultural goods in Argentina on Monday, as a wage strike continued. Also, continued dryness inhibits soybean planting in Argentina, while concerns grow about global soybean supplies next year. Soybean export inspections topped 2.5 million tonnes for the week ending Dec. 17, up 3.1% from the prior week, according to the U.S. Department of Agriculture. “With the weather down in South America, Argentina and Brazil both, and the situation here, I think we’ve got some chances for some decent moves,” said Jack Scoville, market analyst at the Price Futures Group. “(Demand) is still enough to keep us on a very tight ending stocks scenario.” Wheat inched higher as tightened exports from Russia support wheat demand from the United States and other global producers, including Ukraine, where export prices strengthened following Russia’s export tax announcement. Ukraine vowed it would not impose similar export restrictions. Wheat exports climbed to 391,219 tonnes, up 49% from the previous week, according to the USDA. Corn was pressured by rains in Brazil, strengthening the drought-stricken crops competing with U.S. exports despite lower exports sales compared with the prior week. “Weekly exports in corn will stay relatively decent. Does that mean every week has to be good? No,” said Tom Fritz, commodity broker at EFG Group. (Reporting by Christopher Walljasper in Chicago; Additional reporting by Michael Hogan and Colin Packham; Editing by Dan Grebler and Peter Cooney)