Businessman and leading GOP presidential contender Donald Trump is going after Sen Marco Rubio on Twitter, writing Rubio “cannot be president” based upon a Breitbart report that Rubio “would keep Barack Obama’s executive amnesty for DREAMers in place until it was permanently codified through legislation.”

Marco Rubio would keep Barack Obama’s executive order on amnesty intact. See article. Cannot be President. https://t.co/JW5f8OouyA — Donald J. Trump (@realDonaldTrump) November 3, 2015

Trump has been increasingly going after Rubio, as the freshman Senator has begun getting some traction in the polls.

More on Rubio’s previous remarks here.