President Trump was supposed to have until Friday to sign a waiver that would block the renewal of U.S. sanctions on Iranian oil. However, late Tuesday, a White House official indicated that the decision may be pushed until early next week. The holiday weekend may give the White House more time to give congressional notification.

A decision not to waive sanctions may deal a fatal blow to the Iran nuclear deal by putting the U.S. in violation of the international nuclear agreement known as the Joint Comprehensive Plan of Action (JCPOA).

"If he doesn't, it'll be the end of the JCPOA as far as the U.S. role," said one congressional aide familiar with the White House talks.

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If the U.S. fails to maintain its commitments, Iran has threatened to stop allowing the United Nations' nuclear watchdog to inspect its nuclear sites. That would mean the world would no longer be able to monitor and officially verify that Iran is keeping its nuclear program frozen.

The recent popular protests in Iran have captured President Trump's attention and injected a new level of uncertainty into the process. The president's national security team has been supportive of the protests and is now faced with the challenge of convincing the president that it is still worth signing off on allowing the regime to sell its oil and conduct financial transactions free of U.S. sanctions.

Secretary of State Rex Tillerson, Defense Secretary Jim Mattis, chief of staff John Kelly and National Security Adviser H.R. McMaster will meet with the president Thursday to discuss the decision.

They are expected to advise that the U.S. remain part of the nuclear agreement. Over the weekend, French President Emmanuel Macron also urged the president not to violate and thus endanger the deal.

On Tuesday, White House press secretary Sarah Huckabee Sanders said that no final ruling had yet been made. Three other Trump administration officials told CBS News there were a number of factors in play and cautioned that it was not at all certain that the president will heed the advice of his national security team to uphold the agreement. Under that deal, the U.S. agreed to keep sanctions lifted as long as Iran keeps its nuclear program frozen.

The president can withdraw the U.S. from the nuclear deal at any time. At the advice of his national security team last October, the president stopped short of doing that and instead simply notified Congress that he no longer felt it to be in the national security interest. American partners in the deal including Russia, China, Germany, France, the United Kingdom and the European Union breathed a collective sigh of relief that the U.S. did not withdraw. But Mr. Trump warned it remained a possibility.

"In the event we are not able to reach a solution, working with Congress and our allies, then the agreement will be terminated. It is under continuous review and our participation can be cancelled by me as president at any time," Mr. Trump said.

This time, the president's decision will be influenced by whether or not he is satisfied by a proposed legislative fix to a law written by Sens. Bob Corker, R-Tennessee, and Ben Cardin, D-Maryland, that codifies America's participation in the international agreement. He ordered Congress to "fix" that law back in October. Among the tweaks to the U.S. law -- which does not change the actual international nuclear agreement -- would be removing the regular requirement for the president to renew sanctions relief every 90 days.

"It is a manufactured crisis and these are manufactured deadlines," a congressional aide involved with the process told CBS News. "The real goal is to not put a shiny object in front on him (the president) every few weeks."

Aides involved in the process said that their goal now is to have strong enough language ready for a proposed bill that would be sufficient enough to provide National Security Adviser H.R. McMaster with the ability to ask for Congress to have more time to finalize the legislation.

The two senators met with McMaster about the draft language on Thursday and aides say they continue to make progress. The legislation is not complete, but Secretary of State Rex Tillerson told the Associated press on Friday that he was cautiously optimistic.

"I don't want to suggest we're across the finish line on anything yet," Tillerson told the AP.

When Mr. Trump announced the decertification in October he did so in a grand speech at the White House. The State Department is not currently planning a rollout for the announcement on Friday.

At a minimum, a number of congressional aides and U.S. officials indicated that they do expect the president to declare that the JCPOA is not in the national security interest of the United States as he did back in October. That notification was made despite there being no reported evidence that Iran had violated it.

Europeans want to save the deal. When the European Union's High Representative Federica Mogherini met with Tillerson in December she expressed this message loud and clear.

"I have reaffirmed the European Union view that continued implementation of the Iran nuclear deal is a key strategic priority for European security but also for regional and global security," Moghreini said, standing next to Tillerson.

"It was decided that nuclear deal would have been purely on nuclear issues back some 14 years ago, so now dismantling an agreement on nuclear issues that is working, as the IAEA has certified for nine times, would not put us in a better position to discuss all the rest on the country."

The assumption has been that the deal could, technically, stand if the U.S. left. But the loss of the U.S. and its economic might would deal quite a blow to the international agreement and could prompt Iran to pullout.