December milling wheat on the Paris-based Euronext settled 1.75 euros, or 0.9 percent, lower at 198.75 euros ($231.07) a tonne.
It rose earlier to its highest in more than a week at 204.50 euros, buoyed by gains in Chicago, before turning lower after the US Department of Agriculture's (USDA) monthly report.
The USDA surprised traders with a steep increase to its projection for this year's US corn harvest yield to a new record.
It also raised its forecast of global wheat stocks, partly due to a 3 million tonne rise to estimated Russian production.
Expectations that wheat supply will tighten considerably in Russia, the world's top exporter, have contributed to a rally in prices in recent months, although the country's officials have played down talk about possible export restrictions.
"The Russian numbers will no doubt be debated ad infinitum," one futures dealer said of the USDA report.
Very strong Russian exports at the start of the 2018/19 July-June marketing year have fuelled speculation that a supply crunch is developing, and Russian wheat again dominated a tender held by Egypt on Wednesday.
The major importer booked 235,000 tonnes of Russian wheat.
Traders were awaiting results of a tender by Algeria, which should bring fresh sales for French wheat.
France is expected to increase soft wheat exports outside the European Union to 8.5 million tonnes from 8.1 million last season, helped by a harvest that was less affected by severe weather than in other EU countries, farming agency FranceAgriMer said in its first supply-and-demand outlook for 2018/19.
Financial investors raised their net long position in Euronext wheat futures and options in the week to Sept. 7, data published by Euronext showed.
In Germany, cash premiums in Hamburg drifted down in slack demand earlier in the day before the USDA data.
"Buyers were unwilling to follow the strength in Paris seen before the USDA reports," one trader said.
A dearth of export activity after a drought-hit harvest in Germany meant domestic feed demand continued to drive the market, traders said.
Standard bread wheat with 12 percent protein for September delivery in Hamburg was offered for sale down 1 euro at 3.5 euros over Paris December.
Feed wheat in Germany's South Oldenburg market for September/December continued to be offered for sale well over milling wheat at around 217 euros a tonne, with buyers seeking 215 euros.