Israeli, US experts sharply differ about Iran nuclear breakout time

How fast is Iran's nuclear clock ticking? And how soon will time run out. US and Israeli officials disagree.

US and Israeli intelligence experts are in sharp disagreement over the time Iran needs for breakout to a bomb. The Americans say that Iran would need one year between a decision to go from nuclear threshold to nuclear bomb – enough time for preventive action – while the Israelis say the time is much shorter – six months at most. President Barack Obama and US Secretary of State John Kerry, who leads the negotiations with Tehran, insist that America intelligence would detect an Iranian decision to go forward in time to step in and pre-empt it.