The Ukrainian nuclear warheads were supposedly all given back to Russia, plus none of them would have worked without the launch codes which only Russia had. Iran secretly getting more than 150 nukes from Ukrainian stockpiles (without launch codes) in the early 90s seems extremely unlikely. Especially since all Ukrainian secrets are probably known by the West by now.
I'm not sure which source determined the number of 150 units.
Here's an additional mention from January 18, 2008... (thetruthseeker.co.uk)
However the really critical omission, according to an intelligence insider, is that Iran is ready to fight a US led attack and not only with conventional weapons. In fact it is not just trying to develop nuclear weapons, it may already possess them.
According to one source with connections to British Intelligence, Iran has at least 10 nuclear weapons housed separately in reinforced silos under mountains. It also has the means to deliver them in a variety of missiles, some of which are still under development but some already deployed. These include: the Shaheen III, fully operational and capable of hitting Israel and Coalition forces in Iraq (pictured below recent parade in Teheran): the Shaheen IV, still being developed but with the potential of hitting Europe and the UK: and finally the Shaheen V, also still under development but with the potential to hit America’s east coast from Iran.