Representatives from 40 countries, including the hardest-hit nations like Nigeria, Tunisia and Indonesia, will attend the meeting under the title "Uniting for Global Food Security" ahead of a G7 leaders summit in Bavaria starting on Sunday.

As a result of Russia's invasion of top agricultural exporter Ukraine, grain deliveries across the Black Sea have been stalled by minefields and a Russian military blockade of Ukrainian ports.

The crisis has seen food prices soar and contributed to the global spike in inflation.

The United Nations has warned that it is currently affecting poorer African countries the most because of their heavy dependence on Russian and Ukrainian wheat.

German Foreign Minister Annalena Baerbock on Friday accused Russia of using hunger "quite deliberately as a weapon of war" and "taking the whole world hostage".

A global hunger crisis had already been looming "like a life-threatening wave", she said, but Russia's invasion of Ukraine has "turned this wave into a tsunami".

Moscow denies blocking the passage of cargo vessels and blames Western sanctions against Russia for contributing to the food crisis.

Turkey has been spearheading efforts to resume grain deliveries across the Black Sea and this week agreed to pursue talks on how to solve the crisis after a meeting with Russian officials in Moscow.

The Turkish defence ministry said four-way grain talks between Russia, Ukraine, Turkey and the UN could be held in Turkey "in the coming weeks".

Baerbock said Friday's conference would aim to "offer solutions" such as accelerating food exports from Ukraine through new land routes.

Discussions will also focus on increasing aid to the worst-hit countries, though the event is not being billed as a donor conference.