European wheat futures extended losses to hit a 4-week low, sapped by a fall in Chicago as an advancing U.S. harvest weighed on sentiment. Drier conditions in France, after heavy rain in the past month, were also easing worries about damage to crops, although traders continued to monitor possible yield losses in northern and eastern Europe due to persistent dryness. December milling wheat, the most active contract on Paris-based Euronext was down 2.50 euros, or 1.4 percent, at 179.25 euros a tonne at 1546 GMT, after touching its lowest since May 21 at 178.50 euros. After a pullback last week, when worries over tensions between the United States and major trading partners fuelled selling by investment funds, progress in harvesting U.S. hard red winter wheat kept Chicago futures under pressure on June 18.