Secretary of State Rex Tillerson made clear on Wednesday that the Trump administration strongly opposes the landmark 2015 Iran nuclear deal struck by the Obama administration and world powers.

But he also signaled that the US would not immediately tear up the deal, as Donald Trump repeatedly pledged on the campaign trail.

Instead, the Trump administration will conduct a “comprehensive review” of US policy toward Iran, Tillerson said, leaving one of Barack Obama’s signature policies in place — for now.

“An unchecked Iran has the potential to travel the same path as North Korea, and take the world along with it,” Tillerson said. “The United States is keen to avoid a second piece of evidence that strategic patience is a failed approach.”

The remarks follow Tillerson’s notification to Congress on Tuesday that the Trump administration has determined that Iran is complying with the Iran nuclear deal, which put curbs on Tehran’s nuclear program in exchange for sanctions relief. As a candidate, Trump called the agreement the “worst” deal ever made.

Aside from the nuclear deal, Trump accused Iran of destabilizing the Middle East and wreaking havoc in Yemen, Iraq, Lebanon, and Syria.

“The evidence is clear: Iran’s provocative actions threaten the United States, the region and the world,” Tillerson said.

In Yemen, he specifically called out Tehran for devising a "complex Iranian network to arm and equip" the Houthi rebel movement battling Saudi Arabia and its allies for control over the impoverished country. By contrast, President Barack Obama had said Iran's support for the rebels was overstated.

Tillerson did not say why the Trump administration was not immediately pulling out of the Iran deal, but analysts have pointed out that such action would likely provoke Tehran to begin developing its nuclear program again, and it's far from certain that the US would have the global support to rebuild an international sanctions regime in that context. Key US allies and adversaries strongly support the agreement, including Germany, Britain, Russia, China, and France.

So faced with the choice of ripping up the deal immediately, or keeping it in place, the Trump administration has opted to kick the can down the road while voicing its displeasure with the status quo.

The Iran deal "fails to achieve the objective of a non-nuclear Iran; it only delays their goal of becoming a nuclear state," Tillerson said.

For the Trump administration, the hope is that this middle path will prevent Iran from sprinting toward a nuclear weapon while tempering criticisms from Republican hawks in Congress who wanted to pull out of the agreement immediately and reimpose sanctions.

Thus far, the strategy appears to have the support of at least some influential Republicans on the Hill, such as Sen. Bob Corker, the chairman of the Senate Foreign Relations Committee. “Secretary Tillerson made clear that regardless of Iran’s technical compliance with the nuclear deal, the administration is under no illusion about the continued threat from Tehran and is prepared to work closely with Congress to push back,” he said in a statement.

The certification on Tuesday that Iran is in compliance with the deal extends sanctions relief to the country in exchange for continued limits on its nuclear program. The administration now has 90 days to finish its review.