Washington (CNN) Former Secretary of State John Kerry said Sunday that President Donald Trump's decision to pull out of the Iran nuclear deal earlier this year was "a very dangerous and ill-advised move."
Kerry, who was promoting his new book, "Every Day Is Extra," said on CNN's "Fareed Zakaria GPS" that the move "is not based on any broad strategy that is drawing other countries to the table to be supportive of it."
Kerry said he believes Trump's decision to rescind the deal was based solely on a campaign promise.
"I think it represents a campaign promise made by the President in the heat of the campaign, which he followed up on but which has no basis in achieving the goals that the President has set out — if there are goals," said Kerry, who was secretary of state when a framework agreement was reached.
The 2015 Obama-era deal agreed to by the United States, Iran, United Kingdom, France, Germany, China, Russia and the European Union, restricted Iran's nuclear program in return for the lifting of international sanctions.
The former Democratic presidential candidate added that Trump "merely saying this agreement is the worst agreement actually doesn't make it the worst agreement."
"It is in fact the single strongest, single most accountable, single most transparent nuclear agreement anywhere in the world," Kerry said. "What the President has done is simply said, 'I'm going to get out.' And whatever dangers might have existed way down the road if they were trying to break out or something different were happening -- which we would have known and had every military option available to us way down the road, or then or now -- he suddenly rushed to making the way down the road be now, tomorrow," Kerry continued.
By doing so, Kerry argued, the President "has empowered the hardliners in Iran."
"Donald Trump proved them right, and he's put (Iranian) President (Hassan) Rouhani and those who were trying to move to a more rational and reasonable position in a much more difficult -- political and substantively difficult -- position," he said.
The Trump administration's first wave of reimposed sanctions kicked in last month.
In response to the reimposed sanctions, Iran's Supreme Leader Ayatollah Seyyed Ali Khamenei said there would be "no war, nor will we negotiate with the United States."