Members of the world powers negotiating with Iran over its nuclear program admitted having major gaps to resolve the issue, with only a week left before the imposed deadline.

Ministers from the United States, Britain, France, Russia, China, and Germany met on Sunday in Vienna, Austria, to come up with a comprehensive solution to the decade-long dispute on Tehran's nuclear activities.

Like Us on Facebook

But U.S. Secretary of State John Kerry said, "significant differences" remain in the negotiations following a one-week intensive discussion.

"It is vital to make certain that Iran is not going to develop a nuclear weapon and that their program is peaceful. That's what we're here to try to achieve. And I hope we can make some progress on it," Kerry said.

"And obviously we have some very significant gaps still."

British Foreign Secretary William Hague agreed and said issues in Tehran's uranium enrichment program is still unsettled.

"There has been no breakthrough in these talks today," he said.

The world powers have only seven days before the July 20 deadline to finish the deal as agreed on Geneva deal last year.

The initial deal has prompted Iran to suspend some of its nuclear activities in exchange for the lifting of sanctions imposed by the world powers against Tehran.

The West considered Iran's nuclear activities as dangerous that could be used as material for nuclear warheads.

Iran said it was prepared to take steps to guarantee that its nuclear program will be used solely for peaceful purposes.

However, and months after the negotiations, the countries have failed to reach an agreement on long-term solutions to the issue, with some suggesting an extension on the July 20 deadline in order to advance the nuclear talks. That (the extension of the Geneva deal) will have to be discussed If it becomes clear that no other progress can be made," Hague said.

TagsBritish Foreign Secretary William Hague, John Kerry