"The responsibility of the United States, as the strategic ally and main supporter of the Israeli regime in the region, cannot be overlooked in this horrific crime. This act could not have occurred without the authorization and intelligence support of the US," the letter said.
The letter stated that "such a heinous crime, targeting a high-ranking official guest, is a serious infringement on the sovereignty and territorial integrity of the Islamic Republic of Iran." It also constitutes a blatant violation of international law, the letter said.
The Iranian mission called on the Security Council to take immediate action to ensure Israel's accountability for its acts of aggression, including "the potential imposition of sanctions and other measures."
The United States was not part of the recent operation by Israel in Lebanon, US State Department deputy spokesperson Vedant Patel said on Wednesday.
"We were not involved in this mission or operation," Patel said.