Iran nuclear talks: World powers extend 'March 31 deadline' by a day

The self-imposed deadline of March 31 to seal a nuclear deal has been extended by a day by world powers as they negotiate to reach an agreement on Iran's nuclear ambitions in Lausanne, Switzerland.

U.S. State Department spokeswoman Marie Harf said that the progress made by the nations in the last few days merited extending the deadline by a day, ABC News reported. She added that "several difficult issues" still remained.

However, the officials involved in the negotiations have not given any reasons on why more time was required but said that several obstacles remained such as how many centrifuges, which are used to enrich nuclear fuel, might remain at Iran's deep-buried Fordo nuclear reactor, whether Iran should be allowed to continue nuclear research and development for scientific purposes and what to do with the stockpile of enriched uranium that the nation already owns.

Meanwhile, noting that they had "accomplished quite a bit," Iranian Foreign Minister Mohammad Javad Zarif hoped that they could finalize the draft of the nuclear agreement on Wednesday.

Iran and the six world powers namely U.S., U.K., France, Russia, China and Germany had agreed on a Joint Plan of Action (JPA), last year in November, which was an agreement aimed at stopping Iran's nuclear development program in exchange for easing some of the international economic sanctions that have crippled its economy.