Addressing a large and fervent congregation of the people on Friday, Ayatollah Movahedi Kermani said, "The Joint Comprehensive Plan of Action (JCPOA) as an experience proved the US disloyalty."
He reiterated that the West was expected to remove all sanction after six months, but on the contrary it added to them on baseless pretexts.
In relevant remarks earlier on Friday, Iranian Foreign Minister Mohammad Javad Zarif underlined that all parties in the nuclear talks need to remain committed to the JCPOA adopted jointly by Tehran and the six world powers (Russia, China, the US, Britain, France and Germany) in Vienna in July 2015.
"Proper implementation of nuclear agreement is the best option for the western countries, specially the US," Zarif said.
The Iranian foreign minister pointed to recent anti-Iran remarks by the US officials, and said, "Such remarks are ineffective and Obama government imposed several economic sanctions against Iran, but the diplomatic outcome was contrary to what they expected to gain."
In relevant remarks in mid-February, the European Union (EU) and the IAEA reaffirmed that Iran has fulfilled its undertakings under the Joint Comprehensive Plan of Action.
In their joint statement, the EU and the IAEA reaffirmed support for the JCPOA based on their respective mandates.
"EU foreign policy chief Federica Mogherini will remain in close contact with the IAEA regarding continued implementation of the agreement in her capacity as coordinator of the Joint Commission established under the JCPOA," the statement read.
It added that the EU will provide technical support to the IAEA such as equipment and training.
The deal, officially titled the Joint Comprehensive Plan of Action, was reached after hard diplomatic work by the Islamic Republic and the six world powers.
Under the accord, all nuclear-related sanctions on Iran were terminated, and Iran in return agreed to apply certain limits to its nuclear program and provide enhanced access to international monitors to its nuclear facilities.