WASHINGTON (AP) — A leading Republican senator on foreign policy issues says he doesn’t know whether President Donald Trump’s pick to be U.N. ambassador has the expertise and background to capably handle the job.

Trump wants former Fox News reporter and current State Department spokeswoman Heather Nauert (NOW’-urt) to replace Nikki Haley as ambassador. Nauert had little foreign policy experience before taking the State Department post.

The Senate Foreign Relations Committee would consider Nauert’s nomination, and one committee member, GOP Sen. Marco Rubio of Florida, tells CBS’ “Face the Nation” that “I most certainly think she has the ability to do the job well.”

But he adds, “Does she have detailed knowledge of foreign policy to a level that will allow her to be successful at the United Nations? I don’t know.”