The question now confronting negotiators is what should happen to that stockpile as part of a broader agreement between Tehran and Washington. In recent weeks, Kazakhstan has been mentioned as a possible third-party custodian.

Iran's deputy foreign minister says Tehran will discuss uranium enrichment limits and stockpile dilution in upcoming US talks, with indirect implications

The question now confronting negotiators is what should happen to that stockpile as part of a broader agreement between Tehran and Washington. In recent weeks, Kazakhstan has been…