Rob Porter, a White House staffer largely responsible for controlling the flow of information to President Trump, is resigning following allegations of domestic abuse.

Two ex-wives have accused Porter of physical abuse, with one telling news outlets of incidents years ago when Porter punched her in the face and choked her, while another spoke of emotional abuse and being grabbed and pulled from the shower.

Responding to the accusations in a statement read by White House press secretary Sarah Huckabee Sanders, Porter called them "outrageous" and "simply false."

Sanders confirmed Porter's resignation Wednesday, though she said he would not immediately leave his job in an effort to "ensure that there's a smooth transition going forward."

Porter served as the assistant to the president and White House staff secretary. He worked with chief of staff John Kelly on "trying to impose order" in a White House known for feuding staff and disorganization. Beginning after Kelly assumed his chief of staff role over the summer, he directed that all documents that Trump would see should be vetted by both him and Porter.

Sanders said Porter had been "effective" in his job as staff secretary and President Trump and Kelly "have had full confidence and trust in his abilities and his performance."

Porter said photos from 2005 of his first wife, Colbie Holderness, with an apparent black eye had a "reality behind them [that] is nowhere close to what is being described."

"I've been transparent and truthful about these vile claims, but I will not further engage publicly with a coordinated smear campaign," he added.

Outlets including CNN and The Washington Post published the images provided by Holderness on Wednesday. Holderness told the Post, "He threw me down and punched me in the face" during a trip to Italy in 2005.

CNN reported that following their 2003 marriage, Holderness said Porter quickly began to be abusive: "She said that Porter's repeated physically abusive behavior also included throwing her on the bed and forcefully pushing one of his limbs into her body in anger and choking her."

Porter's second ex-wife, Jennifer Willoughby, told CNN that on the honeymoon after their 2009 wedding, " 'He started calling me names, calling me a "f***ing bitch," how I behaved was "f***ing ridiculous" and most of that was instigated around my not having sex with him often enough on our honeymoon.' "

Willoughby took out a temporary protective order in 2010, which according to the Post said that "reasonable grounds exist to believe that [Porter] has committed family abuse and there is probable danger of a further such offense."

Kelly released a statement Wednesday night:

"I was shocked by the new allegations released today against Rob Porter. There is no place for domestic violence in our society. I stand by my previous comments of the Rob Porter that I have come to know since becoming Chief of Staff, and believe every individual deserves the right to defend their reputation. I accepted his resignation earlier today, and will ensure a swift and orderly transition."

Kelly had earlier told the British Daily Mail, "Rob Porter is a man of true integrity and honor," after the tabloid first published allegations of domestic abuse on Tuesday. A day later, Kelly encouraged Porter to "weather the storm" and stay in his job, according to the Post, which said it was Porter who "decided the controversy had become too much" on Wednesday.

Both ex-wives told news outlets that they spoke of the abuse with the FBI last year when the agency was going through a security background check for Porter.

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