Russia's conditions regarding the Black Sea Grain Initiative have not been fulfilled; President Vladimir Putin told his South African counterpart Cyril Ramaphosa in a phone call on Saturday.

Moscow is demanding an end to restrictions on Russian food and fertilizer exports, but this condition has not been met, the Kremlin said during the call on Saturday.

The grain deal runs out on Monday. It could also be suspended until Russia sees its conditions fulfilled.

The United Nations and Türkiye also called on Putin to continue with the agreement. They brokered the original deal last summer, which has been extended several times.

There have been fears since Russia blockaded Ukraine's Black Sea ports that shortages of Ukrainian grain could lead to hunger around the world, as Ukraine is one of the world's biggest grain exporters.

During the call initiated by Ramaphosa, Putin further said the agreement's main goal, to supply African nations in need, had also not been met, the Kremlin said.

Moscow has repeatedly complained that the West has failed to ease sanctions on Russia imposed in an attempt to halt the Ukraine war.

The punitive measures targeting the state-owned Russian Agricultural Bank mean Russia cannot export its own grain and fertilizer to the desired extent. The sanctions also affect freight insurance.

Russia recently said the West had a whole year to resolve this issue.