U.S. Secretary of State John Kerry said on Sunday major differences persist between Iran and six world powers negotiating on Tehran's nuclear program, with a week to go before a deadline for a deal.
"Obviously we have some very significant gaps still, so we need to see if we can make some progress," Kerry said ahead of meetings with foreign ministers who flew into the Austrian capital at the weekend to breathe new life into the talks, reports Reuters.
The United States, Britain, France, Germany, Russia and China want Iran to reduce its nuclear fuel-making capacity to deny it any means of quickly producing atom bombs.
