(CNN) -- With Iran's Foreign Minister Javad Zarif and U.S. Secretary of State John Kerry set to meet in Vienna and the November 24 deadline to the P5+1 and Iran nuclear talks in sight, the White House's ability to provide Iran with significant sanctions relief early in a nuclear deal remains unclear. At the same time, any perceived failure by the U.S. to deliver could complicate, if not poison, what will already be a tenuous post-deal period. U.S. negotiators have not helped their cause. During the latest round of talks in New York, the U.S.'s lead negotiator, Wendy Sherman, promised that "as soon as we [the U.S.] suspend our major sanctions -- which will happen very early in the agreement -- the world will flood into Iran." Her comment was echoed by that of Western diplomats, who likewise urged the Iranians "not [to] underestimate the huge economic relief for their people" in case of a nuclear deal.
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White House's ability to provide Iran with sanctions relief is unclear, writes Tyler Cullis
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Cullis: A poll suggests Iranians do not believe U.S. is willing to lift sanctions
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With ISIS conflict, Obama administration cannot afford hostilities with Iran, he says
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White House involvement needs to accelerate, he writes
Most firms avoid Iran -- even when engagement is permitted -- out of terrified respect for @placeholder sanctions enforcers.