dividends at the negotiating table, where long time nuclear negotiator robert einhorn says iran is driving the harder bargain. >> the iranians may have been concluding the u.s. team was under so much pressure to get a deal that the u.s. and its partners would make all the remaining concessions. >> reporter: this interim deadline was originally intended by the u.s. and its western partners to be an early test of whether a broader agreement is possible and specifically whether iran is willing to make concessions for that broader agreement. these delays could be last minute posturing but at a minimum they leave that question open. >> jim sciutto, thank you so much. in other world news an oil platform in the gulf of mexico turning into a fireball. this was the startling scene as smoke leaking out over the ocean after a fire turned into a full-on inferno. mexico's state oil company says they do not know what sparked the blaze but confirmed four people have been killed.