A famine classification is attributed when an area has at least 20% of households facing an extreme lack of food, at least 30% of children suffering from acute malnutrition, and at least two people for every 10,000 people die each day from starvation or disease linked to malnutrition.
That's the definition for declaring a famine while I imagine 20% are facing an extreme lack of food currently there would need to be 420 a day dying to declare a famine which is not happening yet but I imagine without any aid trucks entering will be the case in the near future.