“There’s not much that’s happened that’s encouraged me,” Rep. Steve King, R-Iowa, said of Trump's pivot in an interview with ABC News.
Trump, who won the GOP primary with his pledge to deport millions of undocumented immigrants with a "deportation force," softened his position earlier this week on Fox News by signaling an openness to a pathway to legal status for some undocumented immigrants.
In an interview with CNN Thursday night, he then appeared to walk back his latest reversal by ruling out legal status for undocumented immigrants who remain in the country.
"There's no path to legalization unless they leave the country," Trump said.
King, who called the initial softening a "mistake," now says Trump's consideration of legal status "gives me an uneasy feeling in my stomach."
“It’s okay to soften some things, but it’s not okay to let people violate the law and be rewarded for it,” he said.
King also said Trump could be in danger of alienating his most fervent supporters by waffling on immigration.
“If you lose the vigorous support of your core base, then it's pretty hard to build a winning coalition to win out in the general election,” he said.
Trump needs to “define amnesty with clarify and reject real amnesty with clarity,” King said, and not continue using language like that of the "comprehensive immigration reformists."
King said he's reached out to Trump campaign manager Kellyanne Conway to share his concerns.
Trump's comments in a Fox News town hall surprised supporters and opponents of immigration reform in the Republican Party.
Former House Majority Leader Eric Cantor, who lost his primary reelection campaign in 2014 to a political novice who ran against his support for immigration reform, likened Trump's new position to the reforms proposed by Jeb Bush, who Trump repeatedly criticized during the GOP presidential primary.
Some Democrats have downplayed Trump's new comments on immigration.
"It's not a pivot or a new approach," said Rep. Luis Gutierrez, D-Illinois. "The voters aren't going to buy it."