“Needless to say, when a media organization is invited by the White House press secretary to attend a presidential briefing, you attend,” he told POLITICO, adding that Rion had been standing in the back of the room to abide by social distancing guidelines.

Herring said Grisham had invited Rion to Thursday’s briefing as well, and that the reporter planned to attend.

Herring said the WHCA was aware of Rion’s invitation from Grisham when it voted to boot OAN from the briefing rotation, where its seat in the room is shared among nine other outlets, nor did the organization indicate that OAN could not accept Grisham’s invitation.

In a tweet Thursday, Rion posted a picture from the very back of the briefing room.

"Physical Update: I am, as I have been these last two days, properly socially distanced from all," she wrote.

Rion's attendance sets off a possible clash with the WHCA, which isn't backing down amid criticism from some conservatives who accuse the association of bias for allegedly singling out a conservative news outlet.

“In order to comply with the social distancing guidelines, and to take steps to ensure the health and safety of the press corps and White House staff, there is no room for reporters who do not have an assigned seat today, or on any given day, to be standing in the briefing room," WHCA President Jonathan Karl said in a statement, calling the decision entirely related to public health. "If somebody is to be a guest of the White House, they should be sitting in the seats to the side which are set aside for White House staff."

Grisham did not respond to requests for comment.