J.D. Vance said today that Donald Trump still prefers a diplomatic solution with Iran and hopes Tehran will take upcoming negotiations seriously. The two sides are scheduled to hold talks tomorrow (Thursday).

“The president has been as clear as he could be: Iran cannot obtain a nuclear weapon (…) He will try to achieve this through diplomatic channels,” Vance said in an interview with Fox News.

The US vice president declined to say whether Washington wants Iran’s supreme leader, Ali Khamenei, to step down from power.

Earlier in the day, the US administration announced new economic sanctions aimed at weakening Tehran’s government and limiting its oil revenues, on the eve of talks between the two sides in Geneva.

The Treasury Department office responsible for sanctions blacklisted four Iranian individuals, several companies, and a dozen vessels. According to an official statement, the tankers are part of a “shadow fleet” that enables Tehran to circumvent the US embargo on crude oil exports and thus “finance its internal repression, affiliated terrorist organizations, and its weapons programs.”

On Tuesday, Trump accused Iran of developing “missiles that can threaten Europe and US military bases” and of seeking to acquire even more advanced weapons systems capable of “striking the United States soon.”