"We cannot be clearer: Sudan is experiencing a starvation crisis of historic proportions. And yet, the silence is deafening," a statement said on Tuesday from the Norwegian Refugee Council and other partners, DPA reported.
Whether Sudan is experiencing what experts describe as a famine is complex, but the aid agencies believe the world cannot wait for an official label before launching more help.
"People are dying of hunger, every day, and yet the focus remains on semantic debates and legal definitions," the statement added.
The criteria for a famine include four out of 10,000 children dying of hunger every day or more than 30% of the population being undernourished.
This is difficult to determine in conflict situations such as in Sudan, where the work of aid organizations is hampered and not all people can be reached.
Rival generals have been locked in a brutal power struggle in Sudan since April 2023. The bloody fighting has displaced more than 10 million people and killed thousands.
Food production has been severely affected. Many fields have been destroyed, mined or the farmers driven away while livestock have been killed.
According to aid groups, more than 25 million people - more than half the population - do not have enough to eat.
Many families eat leaves and insects and only have one meal a day, according to the Refugee Council. Appeals for donations have reached just half of what is needed.