Iran’s Foreign Minister Abbas Araghchi on Sunday said Tehran reserves all options to defend its sovereignty and people after the “outrageous” U.S. attacks on three major nuclear enrichment facilities in the Middle Eastern country.

Iran also launched its 20th wave of missile and drone strikes against Israeli military targets, according to Iran state-owned media Fars. The Israel Defense Forces on Sunday reported sirens blaring due to further Iranian offensives and added it had begun its own missile offensives in western Iran.

The two regional foes have been exchanging attacks since Israel’s surprise attack on Iran last week.

Tehran’s response comes after the U.S. conducted a direct military attack on Iran for the first time, a move that has dramatically ratcheted up geopolitical tensions in the already volatile region.

Araghchi said on social media that the U.S. attacks targeting the Fordo, Natanz and Isfahan nuclear sites would have “everlasting consequences,” adding that “every member of the United Nations must be alarmed over this extremely dangerous, lawless and criminal behavior.”