Wheat prices rose after Russia extended an export ban on grains and high food prices prompted a strike in Mozambique.

Wheat for December delivery rose as high as $7.2475 a bushel in Chicago trading, Bloomberg News reported. Russia, crippled by drought and wildfires in crop-growing areas, said Thursday that its ban on grain exports would last until after the next harvest.

"Russia was for the last couple of seasons a very large part of the world export market and now all of sudden they disappeared," Keith Flury, a grains analyst at Ratzeburg, Germany-based F.O. Licht, told Bloomberg News. "This is kind of the new fundamental shift that not everybody was really ready for."

In Mozambique's capital Maputo, a strike against the increase in food and utility prices entered its second day. At least seven people have died and another 280 have been injured in clashes with police.