The Treasury Department said it was imposing sanctions under additional authorities on five entities including the Atomic Energy Organization of Iran and one individual over the contested nuclear program.

In practical terms, the move is symbolic as the United States already enforces sweeping sanctions on Iran and particularly its nuclear program, whose scientists have also been the target of an assassination campaign attributed to Israel.

But the sanctions are the latest show of pressure by the United States ahead of the talks, which are set to take place Saturday in Oman.

"The Iranian regime's reckless pursuit of nuclear weapons remains a grave threat to the United States and a menace to regional stability and global security," Treasury Secretary Scott Bessent said in a statement, vowing to "disrupt any attempt by Iran to advance its nuclear program."

Iran denies seeking nuclear weapons and US intelligence has not concluded that Iran is pursuing a nuclear weapon, saying only that the clerical state could quickly make a bomb if it chooses to do so.

Trump, who ripped up an earlier nuclear accord during his first time, has voiced hope for a diplomatic solution but has repeatedly warned of the use of force if talks fail.

Israeli Prime Minister Benjamin Netanyahu said Tuesday that military action would be "inevitable" if talks drag on too long.