Russia's war in Ukraine is exacerbating a global food crisis already worsened by COVID-19, US Deputy Secretary of State Wendy Sherman said Tuesday.

Speaking at a UN Security Council meeting, Sherman said Russian warships are blocking access to Ukraine's ports, essentially cutting off exports of grain, and are reportedly preventing approximately 94 ships carrying food for the world market from reaching the Mediterranean.

"Already, food prices are skyrocketing in low and in middle income countries as Russia chokes off Ukrainian exports," she said, adding prices of wheat have risen between 20% and 50% across the Middle East and Africa so far this year.

Sherman noted that nearly half of all Ukrainians are unable to access food, adding people are feeling the war’s effects on food security “far beyond Ukraine’s borders.”

Sherman said the US is "particularly concerned" about countries like Lebanon, Pakistan, Libya, Tunisia, Yemen and Morocco, which she said rely heavily on Ukrainian imports to feed their populations.

On Russian claims that the sanctions imposed by the US and its allies after the war began had raised food costs, Sherman said sanctions are not preventing grain from leaving Ukraine's ports but Russian President Vladimir "Putin's war is."

"Russia’s own food and agricultural exports are not under sanctions by the US or by our allies and partners," she added. "The responsibility for waging war on Ukraine and for the war's effects on global food security falls solely on President Putin."

Russia's war on Ukraine, which started on Feb. 24, has been met with international outrage, with the European Union, US and the UK, among others, implementing stringent economic penalties on Moscow.

Hundreds of global companies have also suspended operations in Russia.

At least 1,179 civilians have been killed in Ukraine and 1,860 injured, according to estimates by the UN, which noted that the true figure is likely far higher.

More than 3.9 million Ukrainians have also fled to several European countries, with millions more displaced inside the country, according to the UN refugee agency./aa