Congressional leaders are split, but not neatly along party lines, over President Donald Trump's decision Tuesday to withdraw from the Iran nuclear deal. Some welcomed the pullout, believing the 2015 accord was unsound, but others worried the U.S. was now in the position of reneging on an international commitment and without a backup plan.

Senate Majority Leader Mitch McConnell, R-Ky., said that the Iran deal "was flawed from the beginning" and that he looks forward to working with the president on the next steps.

"My own view is it's a flawed deal and we can do better," he said. "Clearly there's a next step beyond this and we'll look forward to seeing what he recommends."

But Senate Minority Leader Chuck Schumer, D-N.Y., who opposed the deal negotiated by President Barack Obama's administration and world powers in 2015, said the Trump White House appears to have a slogan but no plan.

"This is a little like replace and repeal — they had these words, they used them in the campaign, and they don't have a real plan here," Schumer said, referring to the failed GOP effort to undo the Affordable Care Act.

The administration — and even Trump himself — briefed leaders ahead of Tuesday's announcement. One top Republican, Sen. Bob Corker of Tennessee, the chairman of the Senate Foreign Relations Committee, also spoke with European leaders and said he looks forward to negotiating better terms of the deal.

"It is disappointing that the administration was unable to reach an agreement with our allies," Corker said. "However, based on conversations I have had in recent days, it is my sense that the administration will move quickly to work toward a better deal."

The committee's top Democrat, Sen. Bob Menendez of New Jersey, said Trump "is risking U.S. national security, recklessly upending foundational partnerships with key U.S. allies in Europe and gambling with Israel's security."

Menendez is among a handful of Democrats who opposed the agreement in 2015. But he said Tuesday that "it is a grave mistake to walk away ... without a plan for ensuring that Iran does not restart its nuclear weapon program, without a strategy for countering Iran's dangerous non-nuclear activities, and without our allies and partners."

The deal put the brakes on Iran's nuclear weapons program for the next decade in exchange for lifting economically devastating sanctions. Trump's decision to reimpose sanctions is expected to provoke a response from Iran that some hope will open negotiations to a better deal. Others, though, say the outcome is uncertain.

House Speaker Paul Ryan, R-Wis., said he hopes during the sanctions implementation period — 90 days for some, 180 days for others — the U.S. will "work with our allies to achieve consensus on addressing a range of destabilizing Iranian behavior_both nuclear and non-nuclear."

Sen. Dick Durbin, D-Ill., called the withdrawal "a mistake of historic proportions."

Trump's action "isolates the United States from the world at a time when we need our allies to come together to address nuclear threats elsewhere, particularly in Korea," said Durbin, the No. 2 Democrat in the Senate.

It's a view shared by some Republicans who opposed the deal.

Arizona GOP Sen. Jeff Flake says allowing Iran to skirt the restrictions imposed on its nuclear program "would be foolhardy." Pulling out of the accord is a mistake, he said, and sends a poor message to U.S. allies.

"We're having enough problems around the world in terms of our reliability," Flake said. "If you're our allies, you've got to be scratching your head, whether it's a trade deal or security arrangements. Is America reliable anymore?"

___

Associated Press writer Matthew Daly in Washington contributed to this report.

___

Follow Mascaro on Twitter at https://twitter.com/lisamascaro