Washington (CNN) A batch of documents reveal frustration among staffers at the Department of Interior over coordinating travel for Secretary Ryan Zinke's wife on an official trip, creating another headache for an administration that's already been criticized for its handling of Cabinet secretary travel.

Through a Freedom of Information Act request, the advocacy group Western Values Project obtained government documents and emails that detail efforts by advance staffers to accommodate a last-minute change in Lolita Zinke's travel itinerary during a May trip to Alaska, Norway and Greenland. The trip was organized by the US Senate, and several spouses were invited to attend.

Staffers for Western Values Project have ties to Democratic politics.

Lolita Zinke was originally scheduled to return to Washington, DC, from Alaska on a military flight, but she requested to stay in Alaska longer with her husband as he was set to attend a Memorial Day ceremony. "Mrs. Zinke prolonged her trip because the Senator invited her to participate in the Rolling Thunder ride and ceremony," Heather Swift, a spokeswoman for the Interior Department, said in an email.

Swift added that Lolita Zinke had paid for her own commercial flight back home from Alaska.

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