'People's lives are being destroyed and shattered by a mere allegation.
"Some are true and some are false", he tweeted.
Porter's swift resignation followed publication in Britain's Daily Mail of a picture of his first wife, Colbie Holderness, with a black eye allegedly suffered when Porter punched her in 2005 while the couple was on vacation in Italy.
"The fact that @realDonaldTrump praised Porter and said not a word about his abusive behavior or his former wives is typical of the WH attitude toward women and abuse", tweeted former New Jersey Republican Gov. Christie Todd Whitman on Saturday".
Porter resigned Wednesday in the aftermath of his two ex-wives describing his alleged abuse. "I think it's a shame". Vice President Mike Pence, traveling in South Korea to attend the opening ceremonies of the Winter Olympics, said he was "appalled" by the allegations against Porter.
Earlier this week, Trump wished Porter well, and reminded reports that Porter "says he's innocent". "He said very strongly yesterday that's he's innocent". Additionally, Hicks reportedly was aware of Porter's record of abuse accusations and still remained romantically involved with him, while also defending him from within the administration.
During an interview Saturday Reince Priebus rejected a report from the New York Times, which suggested the President called him to complain about current chief of staff General Kelly.
ABC News reported that senior members of Trump's administration knew for months that there was a personal issues haunting Porter, according to multiple sources - raising questions among staffers about why he was allowed to continue in such a prominent role in the West Wing.
Porter had kept his new job despite two of his ex-wives, Colbie Holderness and Jennifer Willoughby, telling the Federal Bureau of Investigation that he'd been physically and emotionally violent to them. The White House had called the allegations "very troubling". "And we hope he has a wonderful career", Mr Trump said.
Apart from disbelief, the White House also has showed ambivalence about allegations of mistreatment of women: Steve Bannon was brought on as Trump's chief strategist despite misdemeanor charges in a 1996 domestic violence case.
It was also revealed that Porter had never been granted a full security clearance because of the allegations, even though he served in a position that required him to handle classified material.
Trump has previously defended or sympathized with other men who were accused of abuse, including conservative media titan Roger Ailes and Fox News host Bill O'Reilly.