Responding to a question about Deferred Action for Childhood Arrivals, or DACA, on his hometown radio station WCLO in Janesville, Wisconsin, Ryan said Congress was working on a legislative fix to preserve the problem.
"I actually don't think he should do that," Ryan said of Trump's consideration of terminating the program. "I believe that this is something that Congress has to fix."
Ryan's statement offers the most public support by anyone in the Republican congressional leadership for some sort of legislation to protect the "Dreamers" under DACA.
The popular Obama administration program -- which gives protections from deportation to undocumented immigrants that were brought to the US as children to work or study -- has long been targeted by Republicans as an overreach of executive authority.
Nevertheless, a number of moderate Republicans alongside Democrats support the program and have offered legislation that would make the protections permanent.
Ryan, who worked on comprehensive immigration reform before he became part of House leadership, endorsed that approach in the interview.
"President (Barack) Obama does not have the authority to do what he did ... we've made that very clear," Ryan said in the radio interview. "Having said all of that, there are people who are in limbo. These are kids who know no other country, who were brought here by their parents and don't know another home. And so I