The offer was a significant departure in American foreign policy , given that Iran and the United States severed diplomatic ties after student hard-liners attacked the American Embassy in Tehran in 1979 and held 52 Americans hostage for 444 days .
Iran /location/country/capital Tehran
Iran /location/location/contains Tehran
DT NN VBD DT JJ NN IN JJ JJ NN , VBN IN NNP CC DT NNP NNPS VBD JJ NNS IN NN NNS VBN DT NNP NNP IN NNP IN CD CC VBD CD NNPS NN IN CD NNS .
Iran
LOCATION
Tehran
LOCATION
/location/country/capital
Iran
LOCATION
Tehran
LOCATION
/location/location/contains