"You cannot negotiate with somebody who has a knife in his hand and is putting the knife under your throat," Majid Takht Ravanchi, Iran's ambassador to the United Nations, said in an exclusive interview with NPR.
"That cannot be acceptable by anybody. Any reasonable person cannot accept to have negotiations with somebody who is threatening you."
Takht Ravanchi accused American leaders of unleashing "economic warfare" against Iran in an attempt to isolate the country and forcing it back to the negotiating table.
Yet forging common ground, Ravanchi argued, is surely within the power of the US, adding "And then we noticed that that drone is getting close to our airspace," Takht Ravanchi said.
He said unsuccessful attempts were made by radio to communicate with the drone to warn it away from Iranian airspace.
"And all of a sudden, we noticed that it was entering our airspace," he said. "At that time since it was a spy drone, [we] were left with no other option, but to shoot it down."
Iran was acting in accordance with Article 51 of the UN Charter, a provision allowing military action in situations involving self-defense, he said.
"This was an act of provocation on [the] part of United States, and we asked the international community to demand from the United States to stop these sort of actions, which is somehow endangering international peace and security."
Since the drone was shot down, Iranian officials have recovered portions of the aircraft that "naturally fell down within territorial waters of the Islamic Republic of Iran," Takht Ravanchi added.
"So that shows, by itself, that the drone was shot down within the Iranian airspace," he said.
Asked whether Iran is trying to move toward a confrontation with the US, Takht Ravanchi said, "Definitely not."
"We are not seeking war not only with the US, but also with others," he continued. "It is not in our interest to have a conflict in our region because, to be very frank with you, conflict in our region will be detrimental to all regional countries, the US, and everybody."
Takht Ravanchi said in a war with Iran, there would be no winner or loser. Instead, it would be a "hell, which will be felt by everybody."
He said, Iran needs to be prepared to defend the country's "territorial integrity" at sea, in the air and on the land "against any intrusion by the US, or any other country," echoing a letter he wrote today to the UN secretary-general and the Security Council making the case that his country has a right to self-defense. In the letter, Ravanichi said that the US had committed a "very dangerous and provocative act," by veering into Iranian territory, something he said was a "blatant violation of international law".