Texas Gov. Rick Perry is defending his policy of allowing tuition assistance for illegal immigrants at state colleges and universities, saying the lack of a cohesive federal immigration policy forced his hand.

Perry tells CNBC in an interview that "we need to have an immigration policy that's thoughtful."

The Republican says that when he embraced the concept of tuition assistance in 2001 for illegal immigrants, he believed "it was in the best interest of our state to have these young people educated than kicking them to the curb."

Perry also says that if elected president, he would solve the problem of drug trafficking, illegal immigration and violence along the southern border of the U.S. He declares that "we will stop the drug cartels and we will stop the illegal immigration."