WHEAT - Down 2 to 5 cents per bushel
* Wheat weakens on ample domestic supplies, with traders shrugging off a 120,000-tonne sale to Egypt as the US Agriculture Department said on Friday that wheat stocks as of Dec. 1 stood at a bigger-than-expected 1.999 billion bushels.
* Russia's Agriculture Ministry sees the country's 2018/19 wheat exports at 37 million tonnes.
* Benchmark CBOT March wheat contract firmed early during the overnight trading session but turned lower after hitting resistance as it neared its 40-day moving average.
* CBOT March wheat traded down 3-1/2 cents at $5.13-3/4 per bushel. K.C. March hard red winter wheat was off 2-1/2 cents at $4.91-3/4 a bushel and MGEX March spring wheat was 3-1/4 cents lower at $5.65-1/4.
CORN - Down 1 to 3 cents per bushel
* Corn market seen as technically weak after falling three days in a row to close last week. Corn futures hit their lowest since mid-January during overnight trading.
* CBOT March corn traded down 1 cent at $3.73-1/4 per bushel.
SOYBEANS - Down 2 to 5 cents per bushel
* Traders waited for concrete signs of progress in trade negotiations between United States and China before pushing soybeans higher.
* China struck an upbeat note on Monday as trade talks resumed, but also expressed anger at a US Navy mission through the disputed South China Sea, casting a shadow over the prospect for improved Beijing-Washington ties.
* USDA said that private exporters reported the sale of 120,000 tonnes of soymeal for delivery to Ecuador.
* Support for benchmark CBOT March soybean futures was noted at the 40-day moving average.
* CBOT March soybeans traded down 2-3/4 cents at $9.11-3/4 a bushel.