Iran and world powers on Saturday gave themselves four more months to negotiate a historic nuclear deal after failing to close major gaps in marathon talks in Vienna.

Iran and world powers on Saturday gave themselves four more months to negotiate a historic nuclear deal after failing to close major gaps in marathon talks in Vienna.

"While we have made tangible progress on some of the issues and have worked together on a text (for a deal)... there are still significant gaps on some core issues," lead negotiator and EU foreign policy chief Catherine Ashton said, adding the talks would continue until November 24.

Iranian Foreign Minister Mohammad Javad Zarif had called on the western countries to seize the opportunity to reach a final agreement with Tehran on the latter's nuclear standoff with the West.