President Trump said Thursday that he might do away with the practice of letting national security and diplomatic officials listen in on his calls with foreign leaders following his impeachment over his dealings with Ukraine as laid out in a July 25 phone call with that country's president.

"Why are so many people allowed to listen to your phone calls anyway?" Fox News correspondent-at-large Geraldo Rivera asked Trump during the interview on "Geraldo in Cleveland" on Fox News Radio affiliate WTAM.

"Well, that's what they've done over the years -- when you call a foreign leader, people listen. I may end the practice entirely. I may end it entirely. Sometimes, you have 25 people," the president said.

Trump claimed that Lt. Col. Alexander Vindman, then a National Security Council staffer, was the only person on the call with Ukraine President Volodymyr Zelensky who complained about the conversation.

"First of all, that's very insubordinate. Why wouldn't he go to his immediate, you know, he went to Congress or he went to [Rep. Adam] Schiff or he went to somebody," he said. Trump added that when Vindman left the White House, many people "applauded."

TRUMP TELLS GERALDO THAT 'MANY PEOPLE' IN WHITE HOUSE APPLAUDED AFTER VINDMAN LEFT

Vindman claims he immediately reported the conversation to the National Security Council. He testified before the House Intelligence Committee in the Trump impeachment inquiry last fall and was dismissed from the National Security Council on Feb. 7.

Most Senate Republicans voted to acquit Trump, except Sen. Mitt Romney, D-Utah., who voted to convict Trump of abuse of power. While speaking with Rivera, Trump doubted that Romney acted out of religious conviction when he voted to remove Trump from office.

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"They did reports that he [Romney] brought up his religion very seldom, and all of a sudden he brought up his religion. When did you hear him bring up his religion?" Trump asked. "Look, I got 52-and-a-half votes out of 53. I got 52-and-a-half. I guess if it was the religion, he should have voted for the other half. You know, he voted on one [article] positively and the other negatively," he said.

"He should have probably if it was just the religion, should have voted [the same way] on both if you think about it."