Iran sent a letter to the United Nations accusing the United States of violating the Islamabad Memorandum of Understanding aimed at ending the war and of committing war crimes, Iranian state media reported.
"Almost immediately after the signing of the Memorandum, and continuing to the present day, the United States has not only failed to honor its commitments but has actively and systematically undermined the very foundations of the Memorandum," Iran's permanent representative to the U.N., Amir Saeid Iravani, wrote in a letter to U.N. Secretary-General Antonio Guterres and the president of the U.N. Security Council, according to Iran's state-run IRNA news agency.
The letter alleged violations including renewed U.S. military strikes on Iranian territory, the revocation of licenses for Iranian oil sales, and the establishment of a parallel maritime route through the Strait of Hormuz. It continued U.S. support for Israeli military operations in Lebanon.
"These deliberate, calculated, and sustained actions constitute a grave threat to international peace and security and further demonstrate the United States' complete disregard for its international legal obligations," Iravani said.
Iravani said Iran had formally raised each violation with mediators but that the United States "continued to escalate its unlawful actions."
He said the war on Iran, which began Feb. 28, constituted "unprovoked acts of aggression" by the United States and Israel in violation of the U.N. Charter.
He said the attacks "have included numerous war crimes and crimes against humanity."
Iravani called on the Security Council to take "immediate, effective and decisive measures" to compel Washington to halt its "ongoing unlawful acts" against Iran.
Tensions have escalated between the United States and Iran over the Strait of Hormuz in recent days, with the two sides exchanging attacks despite a Pakistani-mediated memorandum of understanding aimed at ending their conflict and reaching a lasting peace agreement.
A wheat storage silo and another site in Iran's southwestern Khuzestan province were hit by U.S. projectiles overnight, a provincial official said, according to Fars News Agency.
Valiollah Hayati, Khuzestan's deputy governor for security and law enforcement affairs, said a wheat silo in Hoveyzeh County and another site in Dasht-e Azadegan County were struck.
Hayati said no casualties had been reported.
He said assessments were underway and further details would be announced later.
U.S. President Donald Trump said earlier Tuesday that strikes on Iran would continue and intensify in the coming days.
He warned that the United States would begin targeting Iran's power plants and bridges next week unless Tehran returned to the negotiating table.
The latest strikes came amid growing tensions over the Strait of Hormuz, despite the Islamabad memorandum, which Pakistan brokered to help end the conflict and establish a framework for a lasting peace agreement.