"We didn't cover ourselves in glory in how we handled that", Kelly said.
But Kelly's explanation did not fully comport with CNN's extensive reporting on the Porter scandal.
The first accusation brought to his attention about Porter had to do with "emotional abuse", according to Kelly.
Kelly contradicted himself about the timing of Porter's resignation on Friday as well; although the chief of staff first claimed that Porter had resigned following the second allegation of abuse later in the evening on February 6, he subsequently stated that Porter had actually resigned earlier in the day, after the Daily Mail first reached out about the allegations. "The accusation was late in the afternoon and it was simply one of his two former wives had - and this was coming from the press".
The White House continually changed its story about what it knew about the accusations against Porter, and when.
"Based on Federal Bureau of Investigation testimony, White House chief of Staff John Kelly nearly certainly knew about credible allegations of domestic abuse against Rob Porter at least 6 months ago - then recently forced others to lie about that timeline", Mr Scaramucci tweeted on February 13. Over a few hours that day, Kelly said, he had issued a statement in strong support of Porter after Porter's second former wife, Jennifer Willoughby, accused him of abuse.
Kelly, speaking to reporters, went into further detail than he has in the past about his role in the situation.More news: Man Utd ace Lukaku: I never regretted turning down Chelsea
CNN's Anderson Cooper opened tonight by looking at the comments John Kelly made today about Rob Porter and how, well, something seems very off here. The agent referred questions to White House Management and Administration staffer Monica Block.
Porter denies all of the allegations that he engaged in years of physical and verbal abuse.
Scaramucci also referred to Kelly as "General Jackass".
Scaramucci said he thinks Kelly is the one keeping him from visiting Trump, and considering Scaramucci has lobbied to get Kelly fired, that makes a bit of sense. Hicks announced this week that she would soon be leaving the White House. "It won't be immediate, but he is resigning from the White House, but is going to stay on to ensure that there's a smooth transition moving forward".
The Porter situation prompted Kelly to overhaul the White House security clearance system, which included the clearance downgrade of Trump son-in-law and senior adviser, Jared Kushner. He claims he again spoke with Porter. "Inexcusable. Kelly must resign".
Kelly also tried to deflect blame for Porter - despite being a gateway of sensitive and classified documents going to the president - not having a permanent top secret security clearance.
Multiple news outlets have reported that Kelly, along with other top White House staffers, including White House counsel Don McGahn and deputy chief of staff Joe Hagin, knew about some of the allegations for months before they became public. The White House contends that the "full nature" of the allegations did not come out until later.