Update: Trump appeared on Fox News on Monday morning and said he is considering his immigration position, but that it isn't a flip-flop. He said he wanted a "very fair but firm answer."

"We have to be very, very strong when people come in illegally," Trump said. "We have a lot of people that want to come in through the legal process, and it's not fair for them. We're working with a lot of people in the Hispanic community to try and come up with an answer.

"No, I'm not flip-flopping. We want to come up with a really fair but firm answer. That's -- it has to be very firm. But we want to come up with something fair."

Donald Trump launched his campaign on a promise to be very, very tough on illegal immigration — and immigrants. He called Mexican immigrants "rapists" and "criminals." He would later promise to deport every single one of them — even approvingly referencing a controversial 1950s mass-deportation program known as "Operation Wetback." He has in recent weeks prominently featured victims of crimes perpetrated by illegal immigrants.

But according to reports and the suggestions of his top advisers on Sunday, it sounds as if he's considering seriously changing his tune — in what would amount to a stunning flip-flop.

Late Saturday, BuzzFeed and Univision reported that Trump backed away from that rhetoric at a meeting with a group of newly announced Hispanic advisers, appearing open to a plan to deal with the estimated 11 million illegal immigrants that is not deportation.

"Importantly, Trump did not explicitly use the word 'legalization' at the meeting, but sources in the room said they feel it is the direction the campaign is going," BuzzFeed's Adrian Carrasquillo reported.

Univision, meanwhile, reported that three attendees said Trump "plans to present an immigration plan in Colorado Thursday that will include finding a way to legalize millions of undocumented immigrants."

Top Trump advisers were asked Sunday to respond to the reports, and they didn't exactly reject them.

Asked twice whether he was sticking with his plan for a deportation force, newly installed Trump campaign manager Kellyanne Conway deflected and then told CNN that it was "to be determined."

Sen. Jeff Sessions (R-Ala.), meanwhile, said Trump is "wrestling" with how to handle illegal immigrants already in the United States.

"What I'm certain about is that he did not make a firm commitment yesterday, or the meeting the other day, about what he will do with that," Sessions said on CBS News when asked whether Trump still supports deporting all 11 million. "But he did listen, and he's talking about it."

Trump's campaign is playing down the reports and says nothing has really changed. But it clearly has. Even in equivocating and saying it's "to be determined," the campaign is striking a far different tone than Trump has before. Conway was twice given the chance to reiterate that Trump will deport all illegal immigrants, and she didn't.

And, to be clear, that has been Trump's position. Anything else would present a major change from a guy whose primary victory and 2016 campaign writ large have been defined by his hard-line immigration stance. It has been has signature proposal, complete with a Mexico-funded border wall.

In August 2015, when asked on NBC's "Meet the Press" whether he would deport all illegal immigrants, Trump repeatedly responded, "They have to go." In September, he confirmed to "60 Minutes" that was his position, saying they could apply for legalization after being deported.

SCOTT PELLEY: You're rounding them all up?

TRUMP: We're rounding 'em up in a very humane way, in a very nice way. And they're going to be happy because they want to be legalized. And, by the way, I know it doesn't sound nice. But not everything is nice.

Trump repeated his promise of a deportation force in November, even pointing to "Operation Wetback" — a large-scale removal of illegal immigrants under Dwight Eisenhower in 1954 that is now seen as inhumane — though not by name.

And Trump was crystal-clear in a February debate.

"We have at least 11 million people in this country that came in illegally," he said. "They will go out. They will come back — some will come back, the best, through a process. They have to come back legally."

This weekend, though, is not the first time that Trump has signaled he might soften that position. In a February interview with the New York Times editorial board, Trump reportedly said that his plan was negotiable (he later denied that). In June, Trump said he would not describe his plan as "mass deportation."

We don't know what Trump will propose in the days and weeks ahead, but the fact that he's even thinking about it is notable, because his existing plan was clear and unequivocal, presented over and over again.

Trump's positions on the issues have changed before. He is not a model of consistency, to put it mildly. But this issue was so central to his previous appeals that a change in course would truly be striking — the kind of ultraconvenient general election pivot that he has previously avoided and said he wasn't interested in.