PARIS/SINGAPORE - Chicago wheat rose on Friday as Russia's planned annexation of occupied parts of Ukraine kept attention on the risk of fresh disruption to vital Black Sea grain trade.

Corn and soybeans were also firm, also drawing support from a steadying in wider financial markets and adjustments before closely followed U.S. grain stocks data.

The most-active wheat contract on the Chicago Board of Trade (CBOT) was up 1.3% at $9.08-1/4 a bushel by 1150 GMT, while in Europe, December wheat on Euronext was up 0.9% at 355.25 euros ($346.23) a tonne to hold near a three-month high.

President Vladimir Putin was due to proclaim the annexation of territory seized in Moscow's invasion of Ukraine, after the Kremlin warned earlier on Friday that attacks against any of this territory would be considered aggression against Russia.

Tensions over the conflict, also heightened by a leak from Russian gas pipelines to Europe, have raised doubts about whether a UN-supervised shipping corridor for Ukrainian grain will last. "Wheat prices are continuing on their upward trajectory in view of the looming escalation of the Ukraine war," Commerzbank analysts said.

Dry conditions for U.S. wheat planting and the development of the upcoming Argentina wheat crop were also underpinning prices.

CBOT corn added 0.7% to $6.74-1/4 a bushel and soybeans were up 0.4% at $14.16 a bushel. Investors in the agricultural markets were positioning ahead of Friday's U.S. Department of Agriculture (USDA) quarterly U.S. grain stocks and annual small grains reports.

Financial markets stabilised ahead of U.S. inflation data seen as another key gauge of the prospects of further interest rate hikes and a possible economic downturn. Corn and soybean markets were also monitoring progress in harvesting U.S. crops.

Ideal weather this week in much of the U.S. Midwest is expected to bring swift harvest progress.

(Reporting by Gus Trompiz in Paris and Naveen Thukral in Singapore; Editing by Subhranshu Sahu, Sherry Jacob-Phillips and Uttaresh.V)