Kelly told lawmakers that "candidates say things during the campaign that are not informed," said Rep. Luis V. Gutierrez, D-Ill., according to the Los Angeles Times.
"He made it very clear we're not talking about the Trump wall of the campaign -- that was campaign rhetoric," Rep. Lucille Roybal-Allard, D-Calif., said. "There was an understanding the concrete wall does not make sense."
In an apparent response to Kelly's comments, Trump said Thursday on Twitter the wall "has never changed or evolved" from what he initially planned for.
"The Wall is the Wall, it has never changed or evolved from the first day I conceived of it. Parts will be, of necessity, see through and it was never intended to be built in areas where there is natural protection such as mountains, wastelands or tough rivers or water," Trump said.
The president also confirmed the wall would be paid for by Mexico either "directly or indirectly, or through longer term reimbursement."
During the closed-door meeting with members of the Congressional Hispanic Caucus, Kelly also said Trump supports permanent legal protections for undocumented immigrants who were brought to the country as children, including the nearly 700,000 people enrolled in the Deferred Action for Childhood Arrivals program.
In an interview with Fox News Wednesday night, Kelly confirmed the conversation he had with Democratic lawmakers and said Trump "evolved in the way he looks at things."
Kelly pointed out how he previously convinced Trump to go back on his promise to withdraw troops from Afghanistan and explained that the president is now aware that here are large swaths of the U.S.-Mexico border where a wall would be "unrealistic" due to topographical restraints and wild terrain.
"Campaign to governing are two different things, and this president has been very flexible in terms of what's in the realm of the possible," Kelly said.
Kelly added that Trump would approve of a DACA deal if it includes limits on chain migration to include only the nuclear family.
"People that qualify to come into the United States as immigrants, if they're married, their wife could come in, their minor children could come in, but not the parents, not the extended families," Kelly said.
Whether a deal on immigration is close is still not clear, but Kelly said he's optimistic.
"There's no doubt in my mind there's going to be a deal, so long as men and women on both sides are willing to talk," Kelly said.