ISTANBUL -- Iranian Foreign Minister Seyed Abbas Araghchi on Sunday strongly condemned the US military strikes on Iran's nuclear facilities, saying Tehran has multiple options under consideration in response to this "red line" violation.

"The US attack on Iran is an outrageous, grave, and unprecedented violation of the fundamental principles of the UN Charter and international law," Araghchi said at a press conference in Istanbul.

He added that the "lawless" US administration is "solely and fully" responsible for the consequences of its act of "aggression."

"Of course, the door to diplomacy should be always kept open," Araghchi said. "But this is not the case right now. My country is under attack, under aggression, and we have to respond based on our legitimate right of self-defense. We will do so for as long as needed and necessary."

"We are now calculating the damages," he added, urging the world and international organizations, including the International Atomic Energy Agency, to act in accordance with their responsibilities in the face of this "violation of international law."

Araghchi also announced that he will meet with Russian President Vladimir Putin on Monday in Moscow to discuss the latest developments following the US strikes.

Araghchi is in Turkiye to attend the 51st session of the Organization of Islamic Cooperation Council of Foreign Ministers in Istanbul.