President Barack Obama should force on securing the border before bringing up immigration reform, a top Republican said Sunday.

Senate Republican Conference Chairman Lamar Alexander (Tenn.) said that border security would have to precede any conversations on comprehensive immigration reform, for which an outline of legislation was released by Senate Democrats this week.

"When the border's secure, then we can deal with people illegally here, and how they become citizens or not," Alexander said on NBC's "Meet the Press."

Three top Senate Democrats unveiled a plan for comprehensive immigration reform on Thursday. The outline for legislation from Senate Majority Leader Harry Reid (D-Nev.) and Sens. Bob Menendez (D-N.J.) and Charles Schumer (D-N.Y.) seeks to provide a path to citizenship for illegal immigrants, but stresses the need for increased border security first.

The legislation also came amidst a backdrop of tough, new immigration laws in Arizona, which the president has criticized.

"Instead of joking about the Arizona situation and suing Arizona, the president ought to work with the governor and secure the border," Alexander said Sunday. "That's his job, he's the commander in chief; it's a federal responsibility."