Former Secretary of State Colin Powell expressed support for the nuclear agreement with Iran on Sunday, calling the various planks Iranian leaders accepted "remarkable" and dismissing critics' concerns over its implementation.
"It's a pretty good deal," he said on NBC's "Meet the Press."
Powell's comments come days before former Vice President Dick Cheney will speak out strongly against the Iran deal at the American Enterprise Institute. Cheney's speech on Sept. 8 will warn of "consequences for the security interests of the United States and its allies in the Middle East."
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Critics concerned that the deal will expedite Iran's pursuit of a nuclear weapon, Powell added, are "forgetting the reality that [Iranian leaders] have been on a superhighway, for the last 10 years, to create a nuclear weapon or a nuclear weapons program, with no speed limit."
He said the reduction in centrifuges, Iran's uranium stockpile and their agreement to shut down their plutonium reactor were all "remarkable."
"These are remarkable changes, and so we have stopped this highway race that they were going down — and I think that's very, very important," Powell said.
He also pushed back on skeptics who have expressed worries about the ability of independent inspectors to verify that Iran is following the agreement. Powell said that, "with respect to the Iranians — don't trust, never trust, and always verify."
"And I think a very vigorous verification regime has been put into place," he said.
"I say, we have a deal, let's see how they implement the deal. If they don't implement it, bail out. None of our options are gone," Powell added.
On Wednesday, Maryland Sen. Barbara Mikulski came out in support of the deal, giving President Obama the 34 Democratic votes he'd need in the Senate to override a veto of the deal and all but ensuring its implementation.
And Powell noted that, even if the deal did fail in Congress, dozens of other nations who were party to the negotiations have already agreed to it, making it impossible for the U.S. to sit out.
"Even if we were to kill the deal — which is not going to happen — it's going to take effect anyway, because all of these other countries that were in it with us are going to move forward," he said.
"They're all going to be moving forward — we're going to be sitting on the sidelines."
This story originally appeared on NBCNews.com