Story highlights Trump took a much softer tone on undocumented immigrants in a 2012 CNBC interview.

Trump said, "[N]ow we're supposed to send them out of the country, I don't believe in that..."

(CNN) Just four years ago, Donald Trump took a drastically different position on what is now his central issue: deporting undocumented immigrants in the United States.

Since he announced his candidacy last June, Trump has promised to build a wall on the US border with Mexico and at various times said he would, as president, deport all or many of the estimated 11 million undocumented immigrants living in the country. However, in an June 2012 interview with CNBC's Squawk Box reviewed by CNN's KFile, Trump said he didn't believe in deporting undocumented immigrants who, he said, "had done a great job."

Asked about his views on immigrant labor, Trump said, "You know my views on it and I'm not necessarily, I think I'm probably down the middle on that also. Because I also understand how, as an example, you have people in this country for 20 years, they've done a great job, they've done wonderfully, they've gone to school, they've gotten good marks, they're productive — now we're supposed to send them out of the country, I don't believe in that, Michelle, and you understand that. I don't believe in a lot things that are being said."

Trump's comments came in the context of a discussion of the Supreme Court's decision a day before on the state of Arizona's tough immigration law. Trump said "both sides lost" in the ruling, which struck down key parts of the law but upheld a part of the law allowing law enforcement to check the immigration status of a person when enforcing other laws.

A Trump campaign spokesperson did not return a request for comment.

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