Ali Larijani, an advisor to the Iranian Supreme Leader, confirmed that his country is not currently seeking to acquire nuclear weapons, citing a religious fatwa that prohibits it.

In a serious escalation of tensions with Washington, Larijani threatened to develop nuclear weapons if Iran were subjected to a military attack, in response to U.S. President Donald Trump’s warnings of bombing Iran if a new agreement is not signed.

For its part, Russia warned that striking Iran’s nuclear infrastructure would have “catastrophic” consequences.