(CNN) Republican Sen. Mike Rounds defended his colleagues Tuesday, saying they didn't directly reproach President Donald Trump about a staffer's controversial remarks about Sen. John McCain because "we ran out of time."

The controversy started Thursday morning when White House aide Kelly Sadler responded to McCain's opposition to Trump's pick for CIA director by saying "he's dying anyway."

The White House has so far refused to apologize for Sadler's comment about the senator, who announced last year that he had been diagnosed with brain cancer.

The GOP Senate party policy luncheon Tuesday afternoon, which Trump attended, was an opportunity for the members to address the issue with Trump, but they reportedly failed to bring it up. Rounds, who was also in attendance, said that failure to confront Trump was just a matter of time but the remarks are still an important issue.

"It's a very serious issue for a lot of us. You talk about duty, honor and country, you think of John McCain. Today, honesty is the best policy. We ran out of time. We were talking about other issues. The President, in this particular case, he could have been a member of the United States Senate. He was on a roll today. He had a number of issues he wanted to talk about. He touched on a number of very important issues," Rounds said on CNN's "Erin Burnett Out Front."

"Do you have any regrets ... that you didn't bring something up, that was clearly so important to you?" @ErinBurnett presses Sen. Mike Rounds after President Trump isn't asked about John McCain or ZTE during Tuesday's lunch. "We ran out of time" he shares. https://t.co/XERwO7dtEr pic.twitter.com/yV2fVU298y — OutFrontCNN (@OutFrontCNN) May 15, 2018

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