President Donald Trump is privately musing about exiting the North American trade pact, people familiar with the matter said, injecting further uncertainty about the deal’s future into pivotal renegotiations involving the US, Canada and Mexico.

The president has asked aides why he shouldn’t withdraw from the agreement, which he signed during his first term, though he has stopped short of flatly signaling that he will do so, according to the people who spoke on condition of anonymity to describe internal discussions.

A White House official, asked about the discussions, described Trump as the ultimate decision-maker and someone always seeking a better deal for the American people. Discussion about potential action amounted to baseless speculation before an announcement from the president, the official said.

An official in US Trade Representative Jamieson Greer’s office said that a rubber-stamp of the 2019 terms was not in the national interest and the administration intended to keep Trump’s options open and negotiate to address issues that had been identified.