Ted Cruz continued his fight with Marco Rubio over immigration and the Florida senator's initial support of the Gang of Eight bill, which died in 2013.
The Texas senator told CNN's Dana Bash that "border security is national security."
"He has attempted to muddy the waters," Cruz said of Rubio. "But I think that anyone who watched the battle that we had. ... There was a time for choosing, as Reagan put it, where there was a battle over amnesty, and some chose to stand with Barack Obama and Chuck Schumer and support a massive amnesty plan. Others chose to stand with Jeff Sessions and Steve King and the American people and secure the border."
Cruz then pivoted to tie the immigration issue to national security, arguing that the proposed immigration plan in 2013 had inadequate vetting, including the lack of mandated background checks for those entering the country.