Comment by ars

Israel is not an occupying power in Gaza, but rather a warring power. And Article 23 of the 4th Geneva Convention says:

".... are no serious reasons for fearing:

(a) that the consignments may be diverted from their destination,"

i.e. if the warring party believes the supplies will be diverted they have no obligation to supply them.

And that's what is going on here.