"The (UN nuclear agency) IAEA has seen everything and if you're looking for a smoking gun, you've got to wait a long, long, long time before you get one," Mohammad Javad Zarif told an audience at New York University.
Iran and the five permanent members of the UN Security Council -- Britain, China, France, Russia and the United States -- plus Germany have begun drafting a final nuclear accord due by June 30.
Tehran is ready to accept the "highest level of international transparency" available to members of the Nuclear Non-Proliferation Treaty, said Zarif.
"Iran is prepared, within an agreement, to accept the additional protocol and I think with that you will have all the transparency that you need."
More From This Section
If fully implemented, a deal will see Iran dramatically scale back its nuclear activities and submit those that remain to what US President Barack Obama has described the "most robust and intrusive inspections and transparency regime ever negotiated."
About the June 30 deadline, Zarif said: "No time deadline is sacrosanct."
"We want to finish this way before June 30," the minister said.
"We want to use every opportunity, including working around the clock starting next Monday, starting tomorrow actually here in New York, and then next Monday somewhere in Europe, to finalize all the elements."
Iran has fulfilled every detail of its undertaking, Zarif said, since an interim agreement in November 2013 eased the sanctions regime. But he criticized the United States for not doing the same.
"There were many incidents in which I took the heat when there was an apparent American, at least lack of good faith, in implementing its part of the deal when they increased or added new entities to the previous sanctions or similar measures.