January: IAEA confirms Iran is refining uranium to 20 percent fissile purity.
February: U.N. inspectors end talks in Tehran without inspecting disputed military site at Parchin.
March: World powers agrees to renew talks with Iran. Iran says it will let inspectors into Parchin, with conditions.
April: Iranian President Mahmoud Ahmadinejad vows Iran will not surrender its nuclear rights.
May: EU officials say talks in Baghdad with Iran found some common ground.
June: IAEA, Iran start more talks on access for nuclear inspections.