In an interview with ABC News's David Muir, President Donald Trump showed the letter left in the Oval Office drawer by former President Barack Obama. 

“[It] is a custom, but I doubt too many of them were written in this manner," Trump told ABC about the letter. "It was long, it was complex, it was thoughtful and it took time to do it."

Muir confirmed that he has seen letters from past presidents, and the letter from Obama appeared longer than the others. When Muir asked if Trump could share a memorable line from the letter, the president thought for a moment and summarized a section.

"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.