Many in the Senate agree with President Donald Trump's call to decertify the Iran nuclear deal, but a "significant number" recognize the call as a "political maneuver" rather than a strategic decision, Sen. Jack Reed said Friday.

"This undermines our credibility, creates potentially a conflict with our allies," the Rhode Island Democrat told MSNBC's "Andrea Mitchell Reports" program. "It also could have ramifications with the Russians and the Chinese, and then it also misses the point of our greatest crisis of the moment, the North Korean crisis."

The United States is "supposedly pursuing diplomacy" with North Korea, Reed told Mitchell, "but if they're looking and seeing us abandon an agreement we just entered into a few years ago, what's the incentive for diplomacy?"

There has been an argument made with some European allies that once the decision to enact sanctions against Iran comes to Congress, there could be some lawmakers who will try to pile on more against Israel, but Reed said he thinks there are people on both sides who are thinking about the implications of the matter.

"I think the president is thinking this is a free ride, he can do this, he can act tough with his agenda moving forward and Congress will essentially ride to the rescue," said Reed. "I hope that's the case, frankly, because I think abandoning the agreement would be a mistake."

Reed also said there are also concerns about the timing, considering Congress is facing several deadlines on other legislation, including the budget, tax reform, and more.

"I don't know what they'll do," he said. "My sense is they don't want to touch this but it might be thrust upon them."

According to a Reuters report, Iran is willing to talk about its ballistic missile program, which was not included in the nuclear deal, and Reed said he thinks it would be "very helpful" if Iran will negotiate.

"This is the one area where we have them complying," said Reed. "We have cut off a significant existential threat in effect if they had nuclear weapons, and this would be a much more complicated world... I think, though, the president and we're all sort of focused on their disruptive behavior including missiles, including surrogates in many different countries. That we should concentrate on."

Reed also discussed the reports of tensions between Trump and Secretary of State Rex Tillerson, and said he thinks Trump has "created a dysfunctional situation."

"The capacity of the State Department has been reduced," said Reed. "Their budgets have been threatened. Many positions haven't been filled. We do not have an ambassador in South Korea, which is right at the point of our most significant immediate challenge, nuclear weapons in North Korea."

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