King, in an interview with The New York Times published Thursday, defended white nationalism.
Randy Feenstra, a Republican state senator, announced Wednesday that he plans to run against King in 2020.
3 Republican, said King's remarks were "abhorrent and racist and should have no place in our national discourse". "And it's most definitely not the party of Lincoln", McCarthy said.
McCarthy, now the top Republican in the House upon Paul Ryan's departure from Congress, did not elaborate on what actions he planned to take against King, whether it would be to ask for King's resignation, support a primary opponent, or simply censure the Iowa lawmaker.
He continued, "Action will be taken".
McCarthy explained that there are a number of steps he can take to pressure King for his statements.
"I will not stand back as a leader of this party, believing in this nation that all are created equal, that that stands or continues to stand and has any role with us". President Donald Trump was roundly criticized - including by Scott and other Republicans - for his failure to condemn white supremacists following a violent 2017 rally in Charlottesville, Virginia, that left one counter-protester dead.
"Some in our party wonder why Republicans are constantly accused of racism - it is because of our silence when things like this are said", the senator wrote.
"White nationalist, white supremacist, Western civilization - how did that language become offensive?"
"We have made significant progress in our nation, and while there is still work to do, we can not let these intolerant and hateful views hold us back".
"We were very quick to reject those comments" he said on ABC's This Week. "This is a uniquely fractured time in our nation's history, not our worst but far from our best, and it is only together that we will rebuild the trust we seem to have lost in each other", Scott wrote in The Washington Post.
Before the November election, Ohio Rep. Steve Stivers, the chairman of the House GOP's campaign arm, issued an extraordinary public denunciation of him, writing: "We must stand up against white supremacy and hate in all forms, and I strongly condemn this behavior".