Nuclear talks between Iran and six world powers are accelerating as the sides try to seal a deal by the June 30 target date.

After a meeting last week that stretched into the weekend, experts from all seven nations are resuming negotiations Tuesday. They will be joined by senior officials later in the week.

At the negotiating table with Iran are representatives from the United States, Russia, China, Britain, France and Germany. Foreign ministers are expected to join in during the final stage of the talks.

The six world powers want long-term caps on Iranian nuclear programs that could be used to make weapons. Tehran denies any interest in atomic arms and seeks an end to sanctions in exchange for any nuclear concessions.