There were those 3 sophisticated thermonuclear warheads from south Africa that went missing somewhere in Arabia.
And then about 200 Russian Ukrainian 300Kt nuclear weapons that went missing when the former soviet Union collapsed and everything was for sale to the highest bidder.
Considering the Arabs had the means for the highest bid, there is a strong possibility that those weapons are in there possession.
And if need be, they can protect Iran against Israel, since in case of a nuclear war the Arabs know they will suffer the consequences at least of radioactivity, that is why they have prepared themselves for this eventuality too.
The other thing is, that if Israel has 300 nukes and had never tested even one, than Iran might have a thousand or so.
But to compare with tiny Israel is not appropriate, we will take on the US in case of nuclear threats or use.
Everyone knows that Israeli nukes - about 12 in total - were send by the US in the 1973 war in Sinai, no one knows if they are still there or not.
I repeat again,
The Muslim Ummah will prevail.