There is growing optimism that an historic pact to scale back the Middle East country’s nuclear capability can be reached with the so-called P5+1 group comprising the US, UK, France, China and Russia plus Germany after the parties struck a framework agreement in April.

Iran’s Foreign Minister Javad Sarif was quoted as saying by the BBC that “some differences remain, and we are trying and working hard” after the self-imposed deadline for a final deal was pushed back from 30 June.

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