It raised its estimate of soft wheat production in the 28-country EU, to 141 million tonnes from 140.7 million expected last month, now 4 percent above last year's level.

This reflected a combined 2.1 million tonne increase to expected output in Bulgaria, Lithuania, Latvia, Estonia, Hungary, Poland and France.

That offset a 1.8 million tonne cut to production in Germany, Czech Republic, Slovakia, Spain and the UK, it said in a monthly report published on Thursday.

"Yield results for the 2017 harvest are good to excellent in southeast Europe but disappointing in Germany, Czech Republic and Slovakia," it said.

"In terms of soft wheat grain quality, values are good overall in southeast Europe and France, but quality has degraded due to the recent rains in Germany and the central European countries."

After harvesting in France, the EU's top wheat grower, showed better yields and quality than feared given adverse weather spells this year, market attention has shifted to No. 2 EU producer Germany where incessant rain has delayed field work and threatens to damage crops.

Strategie Grains also pointed to concern over grain quality in Poland and the Baltic states following rain, which could particularly affect malting barley, the variety used to make beer and whisky ingredient malt.

It raised its forecast for barley production in the EU by 700,000 tonnes to 58.2 million tonnes, Strategie Grain said, citing a 500,000 tonne combined increase for France, Poland and Hungary, plus smaller gains for the Czech Republic, Estonia, Latvia, Lithuania and Bulgaria.

Crop prospects for maize, which is harvested later in the year than wheat and barley, were also mixed.

Strategie Grains raised its projection of 2017 grain maize production by 100,000 tonnes to 58.9 million tonnes.

That set an 800,000 tonne upgrade to expected output in France and Bulgaria against a 700,000 tonne decline for Hungary, Italy and Spain.

"In early August, growing conditions for grain maize had improved significantly in France whilst remaining satisfactory in Bulgaria and Romania. By contrast, growing conditions had deteriorated in Italy and Hungary due to the hot, dry weather," it said.