President Donald Trump gets 'beautiful letter' from outgoing President Barack Obama

Trump showed the folded letter, addressed to "Mr. President," to ABC News' David Muir during an interview that aired Wednesday. Trump declined to read the actual letter, but said it was "so well-written, so thoughtful."

"I won't show it to you, read it to you, but … (it's) just a beautiful letter," he said.

Trump declined to discuss details in the note, with one exception.

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"He said something that was very interesting to me. He said, 'You know, if I thought your health care plan was going to be better' than his plan – Obamacare – 'I would support it.' And I believe he would," Trump said.

The letter from Obama appeared longer than previous notes that have been made public. The letters are considered private correspondence and are not part of the public record.

"(It) is a custom, but I doubt too many of them were written in this manner," Trump said. "It was long, it was complex, it was thoughtful and it took time to do it."

He said he called Obama with his thanks after reading the note.

"It was stated beautifully that I'm representing a lot of people and I'm carrying on a very important tradition and just do a great job," he said. "He wants me to do a great job."