The Atlantic's editor-in-chief said Sunday that reporting about President Trump’s comments denigrating fallen U.S. service members has only just begun. 

"I would fully expect more reporting to come out about this and more confirmation and new pieces of information in the coming days and weeks," Jeffrey Goldberg said on CNN's "Reliable Sources."

"We have a responsibility, and we're going to do it regardless of what he says," Goldberg added. 

Trump has strongly denied the Atlantic report, which centered on his canceled trip to the Aisne-Marne American Cemetery near Paris in 2018.

The magazine reported Trump canceled the trip because he worried his hair would be disheveled by the rain. 

He also reportedly asked senior staff during a meeting before the planned visit, “Why should I go to that cemetery? It’s filled with losers.”

The Atlantic also reported that Trump referred to U.S. Marines who were killed at Belleau Wood during World War I as “suckers” because they died. 

Portions of the Atlantic report have since been confirmed by multiple news outlets. CNN reported it had confirmed several aspects, also with sources who requested anonymity. 

"We all have to use anonymous sources, especially in a climate where the president of the United States tries to actively intimidate," Goldberg told CNN on Sunday, referring to his decision not to identify sources in the original report. "These are not people who are anonymous to me."

Trump late last Thursday called the sources “liars” while speaking to reporters.

“If they really exist, if people really exist that would have said that, they’re lowlifes and they’re liars. And I would be willing to swear on anything that I never said that about our fallen heroes. There is nobody that respects them more,” Trump said at Joint Base Andrews after a campaign stop in Pennsylvania. 

“So, I just think it's a horrible, horrible thing. It made a great evening into frankly a very sad evening when I see a statement like that. No animal, nobody, what animal would say such a thing?” Trump continued. 

Trump’s secretary of Veterans Affairs, Robert Wilkie, also defended Trump on Sunday when asked about the report. 

Asked on CNN’s “State of the Union” if he had ever heard the president make disparaging comments about veterans or U.S. service members, Wilkie said, “Absolutely not.” 

“I would be offended too if I thought it was true,” he added.