CANBERRA, Oct 25 (Reuters) - U.S. wheat futures hit a three-week high on Monday, supported by strong global demand and concerns about supply shortages.

FUNDAMENTALS

* The most active wheat futures on the Chicago Board Of Trade were up 0.1% at $7.56-3/4 a bushel by 0126 GMT, near the session high of $7.59-3/4 a bushel - the highest since Oct 4. Wheat closed up 2% on Friday.

* The most active soybean futures were up 0.3% at $12.23-1/2 a bushel, having firmed 0.3% on Friday.

* The most active corn futures were down 0.1% at $5.37-1/4 a bushel, having gained 1.1% in the previous session.

* Wheat market grapples with strong export demand as stockpiles are expected to decline in major exporting zones this season.

* In Australia, robust demand for wheat is quickly filling up shipping slots as importers book cargoes ahead of what is expected to be a second year of near-record output.

* Corn draws support from talks of shifting U.S. acres toward soybeans next year due to climbing fertilizer costs, while beneficial rain for planting in Brazil and upward revisions to U.S. and European harvests curbed prices.

MARKET NEWS

* The dollar pared losses on Friday after Federal Reserve Chairman Jerome Powell said the U.S. central bank should begin reducing its asset purchases soon, but should not yet raise interest rates.

* Oil prices rose on Monday, extending pre-weekend gains, with U.S. crude hitting a seven-year high as global supply remained tight amid strong demand worldwide as economies recover from coronavirus pandemic-induced slumps.

* Asian shares started steady on Monday ahead of a week packed with major quarterly earnings announcements, while the dollar hovered near October lows after three weeks of risk-friendly sentiment hurt safe-haven currencies.

(Reporting by Colin Packham; Editing by Rashmi Aich)