Mr Kerry said he and Mohammad Javad Zarif needed to “take stock” ahead of a new round of negotiations on Thursday.
Six world powers want Iran to curb its nuclear programme in return for the lifting of sanctions.
An interim deal was struck in November 2013 but deadlines for a comprehensive deal have since been missed.
The aim now is to reach a high-level political agreement by 1 March and confirm the full technical details of the agreement by 1 July.
Iran is subject to UN economic sanctions amid fears that it is trying to develop a nuclear weapon.
There is strong disagreement between the US and Iran over the latter’s nuclear programme, which Tehran says is exclusively for peaceful purposes.
https://endtime.com/wp-content/uploads/2017/06/80262668_80262667.jpg 351 624 alphatimes https://endtime.com/wp-content/uploads/2020/06/endtime-logo.png alphatimes2015-01-14 00:00:002018-03-28 15:30:25Iran nuclear talks: Kerry meets Zarif in Geneva