Chicago wheat futures jumped over 6% on Friday to hit their daily trading limit on deepening fears that Russia’s invasion of Ukraine will cause massive disruption to supply from two of the world’s top grain exporting nations.

Overnight news of a fire at a Ukrainian nuclear power plant as Russian forces seized control of the site added to investor jitters, sending share prices sliding.

Corn rose to its highest in nearly a decade, as the market also wrestled with the potential loss of millions of tonnes of Ukrainian corn exports.

Soybeans edged lower, pressured by improved growing conditions in South America and profit-taking in vegetable oil markets.

The most-active wheat contract on the Chicago Board of Trade (CBOT) (Wv1) was up by its 75-cent daily limit, or 6.6%, at $12.09 a bushel, a new 14-year high.

The contract had also ended Thursday’s session with a 75-cent limit-up rise.

So far this week the contract is up 40%.

On Euronext, spot March (BL2H2) set a new record high for the Paris-based futures market at 401.00 a tonne, reaching the 400-euro threshold for the first time.

“The demand for wheat on the physical market in (nearby) delivery is unprecedented, as buyers face delivery defaults for Black Sea origins,” consultancy Agritel said.

With Ukrainian ports closed and operators reluctant to trade Russian wheat in the face of Western financial sanctions, buyers are trying to find alternatives.

Algeria will allow suppliers to send French wheat in March, overturning a recent exclusion of France in its tenders, due to disruption to Black Sea supply, traders said on Thursday.

Russia and Ukraine account for about 29% of global wheat exports, 19% of corn exports and 80% of exports of sunflower oil, which competes with soyoil.

CBOT corn (Cv1) gained 1.6% to $7.59-1/2 a bushel, after earlier reaching its highest since October 2012 at $7.72.

CBOT soybeans (Sv1) edged down 0.5% to $16.58-3/4 a bushel.

The U.S. Department of Agriculture on Thursday said exporters sold 337,000 tonnes of U.S. corn to unknown destinations for delivery in the 2021/22 marketing year.

Some traders predict the Ukraine conflict could shift up to 300 million bushels (7.6 million tonnes) of additional corn demand to the United States, said Karl Setzer, a commodity risk analyst for AgriVisor.

U.S. President Joe Biden’s administration is studying whether waiving biofuel blending mandates could help offset a surge in prices for food ingredients such as corn and soyoil, sources said.