While Secretary of State John Kerry resumes talks in Switzerland with Iranian Foreign Minister Javad Zarif, Tehran continues to block efforts by U.N. inspectors to learn about past efforts by the Islamist regime to build nuclear weapons, The Wall Street Journal reported.

Overall, progress has been "very limited," said Yukiya Amano, head of the U.N.'s International Atomic Energy Agency (IAEA). Officials add that an IAEA visit to Iran earlier this month in an effort to resolve the matter achieved no progress.

"We are still not in a position to conclude that all nuclear material in Iran is [for a] peaceful purpose," Amano said Monday in Washington.

Iranian stonewalling – and Washington's apparent reluctance to insist that Tehran cooperate with the United Nations – have led France to take the lead in compiling new demands for Iran. French diplomats in recent weeks appear to have broken from the Obama administration by publicly pushing for tougher terms in any agreement, according to the Journal.

Kerry and Zarif are attempting to reach a political understanding by a March 31 deadline which would constrain Iran's nuclear program in return for lifting Western sanctions.
But Iran's refusal to cooperate with the IAEA "threatens to undermine the prospects for this comprehensive agreement, say diplomats involved in the talks," according to the Journal.

These officials say that the ability of the IAEA and international powers to determine whether Tehran is abiding by a future nuclear deal to prevent it from racing to develop an atomic weapon depends on knowing what it accomplished in its past nuclear work.

The United States and its negotiating partners are attempting to secure Tehran's approval upfront for a "scaled-back" version of an agreement reached by the IAEA and the Iranian government in 2013.  In it, Iran agreed to what officials describe as a "12-step work plan" to resolve questions related to possible nuclear weaponization activities.

Progress, however, has been lagging. According to the IAEA's Amano, Iran has addressed only one of the 12 areas. Amano said that in recent weeks, he has held stepped-up meetings with senior Iranian officials in an effort to breathe new life into the talks. But there was "no progress" made during a trip to Iran this month by IAEA technical staff, he said.

The new plan would attempt to gain access to some of Iran's sites and documents believed tied to past weaponization work.

Under the plan, Tehran wouldn't be expected to immediately clarify all of the unanswered questions raised by the IAEA in a 2011 report on Iran's clandestine nuclear efforts.

A full accounting of Iran's past activities "would be demanded in later years as part of a nuclear deal that is expected to last at least 15 years," according to the Journal.

In other words, it would apparently occur well after all or most sanctions on Iran have been lifted, giving the regime tens of billions of dollars worth of relief.

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