Judges at the International Court of Justice on Thursday unanimously ordered Israel to take all the necessary and effective action to ensure basic food supplies arrive without delay to the Palestinian population in Gaza.
The ICJ said the Palestinians in Gaza face worsening conditions of life, and famine and starvation are spreading.
"The court observes that Palestinians in Gaza are no longer facing only a risk of famine (...) but that famine is setting in," the judges said in their order.
The new measures were requested by South Africa as part of its ongoing case that accuses Israel of state-led genocide in Gaza.
In January the ICJ, also known as the World Court, ordered Israel to refrain from any acts that could fall under the Genocide Convention and to ensure its troops commit no genocidal acts against Palestinians in Gaza.
In Thursday's order the court reaffirmed the January measures but added Israel must take action to ensure unhindered provision of basic services and humanitarian assistance including food, water and electricity as well as medical supplies and medical care to Palestinians throughout Gaza.
The judges added that this could be done "by increasing the capacity and number of land crossing points and maintaining them open for as long as necessary". The court ordered Israel to submit a report in a month after the order to detail how it had given effect to the ruling.
