breaking his leg a bike ride last month. kerry and his iranian counterpart have until tuesday to finalize a nuclear agreement. state correspondent margaret brennan is traveling with kerry. >> i think it's fair to say that we're hopeful. >> reporter: secretary of state john kerry is under pressure to deliver president obama's chief foreign policy goal-- a nuclear accord with iran. this week, iran's supreme leader made that job more difficult publicly stake out several hard lines. nuclear inspectors would not be allowed to inspect military sites, a key demand from the u.s. and all financial sanctions on iran should be lifted immediately, not gradually as the u.s. has proposed. and there's pressure at home too. several former obama aides warned in a recent letter that the emerging deal, "may fall short of meeting the administration's own standard of a good agreement." james jeffrey, the president's former ambassador to iraq signed