Washington (CNN) The current husband of one of Rob Porter's ex-wives emailed the FBI last January expressing concern that a close friend of the former White House aide was "actively working to quell" background check issues.

Skiffington Holderness, the current husband of Porter's first ex-wife, Colbie Holderness, said in an email to the FBI obtained by CNN that he had several conversations with Porter's friend, Bryan Cunningham.

The email details those conversations, including one in which Cunningham allegedly reacted positively when Holderness said his wife was not inclined to talk to the FBI regarding Porter's background check. Cunningham, according to the email, said "that was good," she was "not obligated" to speak with the FBI, and that they should "bury the past."

Porter, President Donald Trump's staff secretary, resigned abruptly on Wednesday after allegations of domestic abuse from two of his ex-wives emerged publicly.

Reached on the phone on Thursday, Cunningham denied that he had conversations with Skiffington Holderness about Porter's background check, with the exception of one time when he asked that Colbie Holderness send some contact information to Porter related to the background check.

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