Foreign sources debate from time to time the size of Israel’s nuclear arsenal, which is estimated at anywhere between 100 and 400 warheads (*). In a recent interview with Time, ex-president Jimmy Carter – who has read a few intelligence reports over the course his life – said that Israel has around 300 nukes.
Asked by the magazine “What do you think it means that Iran seems to have its first nuclear fuel rod?” Carter answers:
Well, of course, the religious leaders of Iran have sworn on their word of honor that they’re not going to manufacture nuclear weapons. If they are lying, then I don’t see that as a major catastrophe because they’ll only have one or two military weapons. Israel probably has 300 or so.
(*) This information is based on Avner Cohen’s summary of several analyses regarding the size of the Israeli arsenal in The Worst-Kept Secret: Israel’s Bargain with the Bomb, Columbia 2010, page xxvii. According to foreign sources, Israel also has sea-based second strike capabilities (ibid).