The high profile negotiations are expected to continue until at least July 15.
Michael Mann, spokesperson for the EU foreign policy, says both Iran and the major powers should show seriousness to narrow differences in order to strike a final deal.
“Both sides will have to come determined to narrow the differences,” Mann told the Tehran Times and Mehr News Agency.
The two sides have set July 20 as the deadline to reach a final deal.
Mann said the European Union trio (Britain, Germany and France) along with the U.S., Russia and China were working hard to make the talks bear fruit.
“The E3/EU+3 is determined to reach a comprehensive agreement,” he noted.
The spokesman also claimed there were “no” differences between the six powers in their approach toward Iran.
He also refused to comment on differences between Iran and the major powers on the content of the final deal. “We do not talk publicly about the content of the negotiations.”
He also confirmed reports that the Western countries in six-nation group want Iran cut down the number of uranium centrifuges in operation, saying, “That will be part of the negotiations.”