Interior Secretary Ryan Zinke on Friday defended his decision to use chartered flights on a handful of occasions, and said that for most of his flights, "I fly coach."

Zinke said the charter flights are used when Cabinet members face circumstances that force them to use private flights, and said he would continue to use chartered flights when needed for "official duties," he said at the Heritage Foundation. He was speaking specifically on using military flights to travel at the behest of the president.

Politico reported Thursday that Zinke had spent $12,000 on chartered private flights. He was the third Cabinet official to have used chartered and military flights to move about the country. Typically, Cabinet secretaries fly commercial.

Zinke called the news story "a little BS," explaining that his ethics officer thoroughly evaluates all his flight plans to ensure he is "above the law."

Zinke remarked ahead of his speech at the conservative Heritage Foundation in Washington: "I'd just like to address, in the words of General [H. Norman] Schwarzkopf, 'a little BS' on travel."

"Since being sworn in, I've used a charter on three occasions," Zinke said his speaking engagement. "The first occasion was being invited on a bipartisan congressional delegation by the Senate Energy and Natural Resources Committee to the Arctic Circle."

The second flight was to meet the governor of Montana and to speak at the National Governors Association meeting.

The third flight was a trip to the U.S. Virgin Islands to attend the 100th anniversary of the transfer of power from Denmark to the United States.

He also added that he took a military flight to survey fire crews in Montana.

Before Zinke's flights, EPA Administrator Scott Pruitt was the second official to be found to have used chartered and military aircraft to move across the country. But the EPA has said it's not normal for the current EPA chief to move about the country this way on the taxpayer's dime.

The Washington Post reported that Pruitt took four non-commercial flights since February, costing $58,000.

The EPA said there were extenuating circumstances that led Pruitt to use a chartered flight. After exhausting all other options, he was forced to take a federal chartered flight to New York, to make a connection at JFK for a delegation trip to Europe.

But Zinke and Pruitt used the services minimally when considering that Health and Human Services Secretary Tom Price spent $400,000 on at least two dozen private flights. The Price revelation began the increased scrutiny of flight record that resulted in the Pruitt and Zinke discoveries.