Iran nuclear talks friction has Fester

With a little more than 24 hours before the deadline for the negotiating parties to reach a political agreement to end Iran nuclear 's weapons program have the most controversial issues not yet resolved in the negotiations.

Iran nuclear talks

The negotiators agreed on the number of centrifuges still could not remain in Iran if Iran will have the opportunity, for the purposes of nuclear research and development scientists continue, and what to do is enriched uranium reserves already own online deeply buried nuclear reactor Fordow, said Today officials.

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In what many observers as there is an optimistic view of degradation at the end of last week, spokeswoman Marie Harf, the State Department said agreement "50-50" chance, could in principle be achieved. Speaking to reporters today at a conference in Lausanne, Switzerland, Harf said the mood is "serious", but "there is still a way to" reach an agreement.

"It's like moving the pieces around," Harf said. "We need to find the right combination."

Although the next deadline is tomorrow, there is nothing to say that talks must stop when time passes, according to the State Department. The Joint Action Plan runs technically to November 30 June.

"On April 1 is no such thing happened," Harf said.

However, it is not known to resume talks if a tentative agreement is not reached before 31 March.

Secretary of State John Kerry leads the negotiations in Switzerland. State Department officials said they hoped to Boston on Monday for a ceremony for the new rear Edward Kennedy -Institute honor of the late Senator from Massachusetts, who was a close associate and friend of Kerry.

President Obama explains the lack of Kerry at the ceremony and quoted John F. Kennedy, a summary of the nuclear negotiations with Iran.

"Let us negotiate, never fear. But we should not be afraid to negotiate," Obama said.

Meanwhile rejected the White House spokesman Eric Schultz some of the sticking points in the negotiations, print on reports that Iran does not fulfill his obligation to export much of their inventory.

"The idea that there is an agreement that is supplied to Iran not true," Schultz said. "Nothing is agreed until everything is agreed".