WASHINGTON - As the United States Senate returned to session for business on Monday, one of its duties was to pay tribute to the late Sen. John McCain.

Georgia's senior senator, Johnny Isakson, spoke for about ten minutes, recounting special memories of his close friend and colleague.

In comments that some may have said were directed at President Donald Trump, Isakson challenged those who would disparage McCain's legacy, saying they "deserve a whipping."

"I'm trying to elevate John McCain. John was better than me, and I know it. He was the best of my generation. John McCain was and is a great human being. I don't know what's going to be said in the next few days about John McCain by whomever it's going to be said; I don't know what's going to be done. But anybody who, in any way -- tarnishes the reputation of John McCain, deserves a whipping. Because most of the ones who would do the wrong thing about John McCain didn't have the guts to do the right thing when it was their turn," Isakson said, in part. "So I would say to the president or anybody in the world, it's time to pause and say 'this was a great man; he gave everything for us.' We owe him nothing less than the respect he earned."

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Isakson's comments came among a flurry of honors to the man that many have called a statesman and an American war hero.

After a day of silence from the White House on McCain and significant criticism from veterans groups and others of the decision to raise the US flag at the executive mansion to full staff early Monday as other flags around Washington remained at half-staff in honor of McCain, Trump issued a statement Monday evening.

"Our hearts and prayers are going out the family of Senator John McCain," Trump said Monday evening during a dinner with evangelical leaders. "We very much appreciate everything that Senator McCain has done for our country."

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Federal law only requires flags to be flown at half-staff for two days following the death of members of Congress, however, presidents have signed proclamations extending the honor for prominent people until burial. Trump himself has signed orders previously, including one for former first lady Barbara Bush in April.