Donald Trump has said the US does not "need a deal with Iran" and directed his vice-president to focus on domestic issues.
It comes after reports JD Vance was considering face-to-face peace talks with a hard-line Iranian security official.
Mr Vance's office did not immediately respond to a request for comment.
Donald Trump says the US does not need a deal with Iran and has directed Vice-President JD Vance, who has played a role in efforts to resolve the war, to focus "his complete and total attention" on alleged crime and corruption in Democratic-run cities and states.
Mr Trump's directive came a day after The Wall Street Journal reported that Mr Vance was considering face-to-face peace talks with a hard-line Iranian security official and a week after the vice-president blamed the costly war with Iran for Republicans' midterm elections drubbing.
Mr Trump's comments marked a shift in tone after he had suggested in recent weeks that Iran would be more willing to strike a deal in the eight-month conflict after the US elections.
"We don't need a deal with Iran. Those days have long since passed. We've got their money, Hundreds of Billions of Dollars, and we've got their Strait!"
