Stephen K. Bannon, Mr. Trump’s senior adviser, is pressing the president to officially pull the United States from the landmark accord, according to energy and government officials with knowledge of the debate. But, they say, he is clashing with Secretary of State Rex Tillerson and the president’s daughter Ivanka Trump, who fear the move could have broad and damaging diplomatic ramifications…

While the president cannot, as Mr. Trump suggested, unilaterally undo a 194-nation accord that has already been legally ratified, he could initiate the four-year process to withdraw the world’s largest economy and second-largest climate polluter from the first worldwide deal to tackle global warming. Such a move would rend a global deal that has been hailed as historic, throwing into question the fate of global climate policy and, diplomats say, the credibility of the United States…

As Mr. Trump and his advisers weigh their Paris options, one proposal is gaining traction, according to participants in the debate: Mr. Trump could declare that the Paris agreement is a treaty that requires ratification by the Senate. The pact was designed not to have the legal force of a treaty specifically so that it would not have to go before the United States Senate, which would have assuredly failed to ratify it.

“If there are camps forming in the White House, then let the people decide, the elected representatives,” Mr. Pyle said. “Let’s put the question to them.”