Donald Trump on Thursday slammed Iran for violating "the spirit" of a deal curbing its nuclear program, weeks before the US president must decide whether to stick by the agreement.
"The Iran deal is one of the worst deals I've ever seen, certainly at a minimum the spirit of the deal is atrociously kept," Trump said aboard Air Force One.
"The Iran deal is not a fair deal to this country. It's a deal that should not have ever been made," he added, tearing into the Obama-era accord.
The United States on Thursday agreed to continue for now to exempt Iran from nuclear-related sanctions but slapped new measures against targets accused of cyber attacks or fomenting militancy.
"We are not going to stand what they are doing with our country. They've violated so many different elements and they've also violated the spirit of that deal," Trump said.
On October 15, Trump is due to decide whether Iran has breached the 2015 nuclear agreement, and critics fear he may abandon an accord they think prevents Tehran from building a nuclear bomb.
But the president would not be drawn on whether he has already made a decision.
"You'll see what I'm going to be doing very shortly in October."
Critics say Trump abandoning the deal would pave the way for Iran to resume nuclear enrichment and would send a signal to North Korea and other proliferators that a diplomatic solution can be scrapped at the president's whim.
"The consequences of a unilateral withdrawal from the deal would be disastrous, isolating the United States while risking a second nuclear crisis and a disastrous war," said Trita Parsi, president of the National Iranian American Council and a vocal supporter of the agreement.