State Department spokeswoman Jen Psaki said Kerry met with Mohammad Javad Zarif in Munich this morning.
Details of the talks weren't immediately available.
Six world powers and Iran reached a first-stage agreement in November that curbs some Iranian nuclear activities in return for a partial easing of sanctions choking the country's economy.
Implemented January 20, that accord will be in effect for six months while further negotiations on a permanent agreement are held.