(This post was last updated at 8:44 a.m. ET.)

Just hours before a self-imposed deadline, Iran and six world powers said they would not extend a deadline but they would keep working toward a deal over Iran's nuclear program for the next few days.

Reporting from Vienna, where the talks are taking place, NPR's Peter Kenyon says both sides — Iran and the so-called P5+1, which consists of the U.K., China, France, Germany, Russia and the United States — are saying they will not be pressured into accepting a bad deal. Peter filed this report for our Newscast unit:

"EU foreign policy chief Federica Mogherini says Iran and six world powers are not extending the July 7 deadline, just interpreting it with a certain flexibility. Both Iran and the U.S. have said getting the right nuclear agreement is more important than any single deadline."If they do manage to finish by early Thursday, negotiators could still deliver a deal to Congress by their July 9 deadline. If they don't, Congress gets an extra 30 days to weigh in on the agreement. Many members of Congress describe the accord as not strong enough."

Al Jazeera reports that Iranian officials say the two sides are divided by a few thorny issues. Chief among them is whether U.N. sanctions on Iran's ballistic missile program should be lifted.

"The Iranians want the ballistic missile sanctions lifted. They say there is no reason to connect it with the nuclear issue, a view that is difficult to accept," an unnamed Western official told Reuters. "There's no appetite for that on our part."

Of course, this cuts to the heart of what's at stake in these negotiations: Western powers are trying to keep Iran from developing a nuclear weapon, while Iran has always insisted that its nuclear program has been used only for peaceful purposes.

The two sides agreed to an interim deal that curbed some parts of Iran's nuclear programs in November 2013. That deal set a July 2014 deadline for a broader deal. The deadline was then extended to November. After that deadline was missed, Iran and six world powers announced that they had reached a framework agreement in April.

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