It was an idea way back when, according to “this”:http://history.state.gov/historicaldocuments/frus1969-76ve08/d227 April 1976 account of a meeting b/t SecState Kissinger and Pakistani Ambassador Yaqub-Khan.
After Kissinger explained that “[m]ost of my preoccupations these days have to do with avoiding criminal charges,” the ambassador handed him a letter from the Pakistani prime minister which included an offer to multilateralize Pakistan’s reprocessing facility.
When Kissinger asked “What countries would you have in mind?,” the ambassador replied: “Iran.”
Even more remarkable, from my point of view, is Kissinger’s follow-on suggestion:
bq. How about Israel? You would get a lot of Congressional support if you would invite Israel to participate. Let me study this further.