Story highlights "There's no path to legalization unless they leave the country," Trump said

But he declined to clarify whether he would forcibly deport all of the undocumented immigrants in the US

Washington (CNN) Donald Trump ruled out Thursday a pathway to legal status for undocumented immigrants in the United States, walking back comments he made earlier this week in which he appeared open to the idea.

But the Republican nominee declined in an interview with CNN's Anderson Cooper to clarify whether he would still forcibly deport the estimated 11 million undocumented immigrants in the US -- a major tenet of his immigration platform -- after he suggested this week he was "softening" on the idea.

"There's no path to legalization unless they leave the country," Trump said after an event in Manchester, New Hampshire. "When they come back in, then they can start paying taxes, but there is no path to legalization unless they leave the country and then come back."

Trump said that on his first day in office, he would authorize law enforcement to actively deport "bad dudes," such as those who have committed crimes, which he said numbered "probably millions." But he declined to flatly say whether he would round up other undocumented immigrants, stressing that once the initial deportations occur, "then we can talk."

"There is a very good chance the answer could be yes," Trump said when asked if he would deport those who have lived here peacefully but without papers. "We're going to see what happens."

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