VIENNA (AP) — Iran said it has built and will activate a third nuclear enrichment facility, ratcheting up tensions with the U.N. on Thursday immediately after its atomic watchdog agency censured Iran for failing to comply with nonproliferation obligations meant to prevent it from developing a nuclear weapon.

“The Islamic Republic of Iran has no choice but to respond to this political resolution,” the Iranian Foreign Ministry and Atomic Energy Organization said in a joint statement.

The censure by the International Atomic Energy Agency, its first in 20 years overIranian non-compliance, could set in motion an effort to restore sanctions on Iran later this year.

U.S. President Donald Trump had previously warned that Israel or America could launch airstrikes against Iranian nuclear facilities if negotiators failed to reach a deal on Iran’s rapidly advancing nuclear program. A sixth round of Iran-U.S. talks is scheduled to begin Sunday in Oman, and as tensions simmer some American government staffers deemed nonessential have begun leaving the Gulf region.