There are indications by at least one recent article  written by Dennis Ross, a Washington insider for many years, that Obama with tacit support of Israel may agree to some level of enrichment in Iran. Provided the “break out” period is very long, perhaps in terms of months or even years but not days.
Advertisement from the 1970s by American nuclear-power companies.
Break out period is usually defined as the amount of time it takes for a country to enrich enough bomb grade nuclear material for at least one crude nuclear weapon, after IAEA inspectors and their equipment have been kicked out of the country. Two factors control the break out period:
Since Iran’s highest enrichment level is 20%, the threshold amount of this level of enrichment needed for one bomb is usually considered to be 250 Kg, if further enriched to the 90% purity level. Therefore, a major component of the break out period is to make certain that Iran does not have this critical mass. As the recent IAEA reports suggest, Iran has kept the amount of readily convertible 20% nuclear material below this threshold of 250 Kg.
It should not be a surprise that the P5+1’s latest proposal to Iran is focused on halting and removal of the 20% nuclear material, to prolong the break out period from days to months, with current number and type of centrifuges installed in Iran. However, the break out story does not end there, even if Iran and the P5+1 reach an agreement on the 20% material.
Most likely the US will want to put a limit on the tonnage of 5% nuclear material, also called Low Enriched Uranium (LEU) that Iran can store domestically. The current 10 tons of LEU in the possession of Iran could make at least 5 bombs after additional processing steps to 20%, 60%, and ultimately the 90% level enrichment. Starting from the 5% material the break out period will be pushed back considerably as compared to the 20%, if the current types of centrifuges are used. In recent months the facts on the ground has changed, because Iran has made significant progress in terms of the total number of centrifuges of the older kind (IR1) and the efficiency of the newly installed models (IR2m) that are 3 to 6 times more powerful than the older ones.
Under Article IV of the NPT there are no provisions for the amount of enriched nuclear material in term of total weight or the level of enrichment. Also, nowhere in this treaty agreement the type or efficiency of centrifuges has been discussed. Member countries have the right to use the best technology they deem appropriate in order to make the enrichment process more cost effective and efficient.
Judging from recent comments by various officials from Iran and Russia, it seems that if Iran is given enough incentives they will forgo the 20% enrichment level, greatly helping with the break out period concerns of Israel and US. But putting limits on the number and type of centrifuges is a far more difficult goal to achieve and it is very unlikely that even Rohani with his moderate political skills can muster support domestically for such a limitation which is clearly outside Iran’s rights under NPT.
So the real question is that if the US bottom line for Iran is to have a fully watered down enrichment capability that provides only a face saving measure during these negotiations without any technological or industrial advantages, can the Islamic Republic live with a Mickey Mouse enrichment program at the end?
... Payvand News - 03/25/16 ... --