Although not certain, there is a rumour that Israel was the sixth country in the world that managed to research and develop their own nuclear arsenal. However, they did not confirm that fact. Still, a lot of sources claim that they managed to prepare fully working nuclear warheads in 1966. In spite of such early dates, Israel has not joined the NPT. Up to this day, they do not confirm nor deny the possibility of having nuclear arsenal. As a result of that, Israel is said to apply quite effective, yet affordable deterring policy.
According to many organizations, the estimated numbers of nuclear weapons that Israel possesses varies from 80 up to even 200 ready to be launched nuclear weapons. What is more, there are also rumours that Israel managed to prepare special missiles that can be operational from submarines.