Updated

A House committee is demanding that 15 federal agencies fully account for senior officials' travel following reports of costly plane travel by Trump Cabinet secretaries.

In letters sent this week, the House Oversight and Government Reform Committee threatened to subpoena the Agriculture and Justice departments by the end of the month if officials fail to provide all the information requested on the use of government-owned aircraft for personal travel or private aircraft for official travel.

The panel said 13 other departments and agencies, including the White House, have only partly responded to its requests.

The House committee is investigating air travel following reports that Health and Human Services Secretary Tom Price used pricey charters when cheaper commercial flights were available. Price resigned last month.

That Sept. 26 request from the committee sought passenger names, destinations, explanations and cost of the government-owned and private aircraft travel.

For all the departments and the White House, the oversight committee also requested additional travel information for the time period of Jan. 1 to Jan. 19.

Such detail is needed "to help determine whether new policies or regulations need to be enacted or perhaps to even change the nature of appropriations to your department," the letter reads.

Travel details were initially due Oct. 10; the panel set a new deadline of Oct. 31.

The 13 departments and agencies deemed to have only partially responded to the committee's request are the White House, the departments of Defense, Education, Health and Human Services, Homeland Security, State, Treasury, Transportation and Veterans Affairs, as well as the Environmental Protection Agency, NASA, the U.S. Agency for International Development and the Small Business Administration.

Several Cabinet members have faced questions about travel since Price resigned.

They include Interior Secretary Ryan Zinke, Energy Secretary Rick Perry and EPA chief Scott Pruitt, who have acknowledged the use of government or private flights costing tens of thousands of dollars. The Cabinet officials have said the trips were pre-approved by ethics officials and appropriate.

At the VA, Secretary David Shulkin is being investigated by the inspector general for a 10-day trip with his wife to Denmark and England to discuss veterans' health issues. Travel records released by VA show four days of the July trip were spent on personal activities, including attending a Wimbledon tennis match. The VA has not released cost information in response to media inquiries or a request by Sen. Jon Tester, the top Democrat on the Senate Veterans Affairs Committee, saying Shulkin traveled on a commercial airline and his wife was approved for "temporary duty" travel expenses, which entitled her to airfare and meals. On Thursday, the VA disclosed that while Shulkin's wife, Merle Bari, was eligible for per diem expenses, she "did not accept it."

"VA paid for her plane ticket only," said VA spokesman Curt Cashour. He did not respond to a renewed request for cost breakdowns.

The 10 agencies deemed by the House committee to have provided all the previously requested information are the departments of Commerce, Energy, Housing and Urban Development, Labor and Interior, as well as the General Services Administration, National Science Foundation, Nuclear Regulatory Commission, Office of Personnel Management and Social Security Administration.

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Associated Press writer Matthew Daly contributed to this report.