MS NOW host Lawrence O’Donnell on Tuesday said President Donald Trump has a tell that reveals when he’s lied.

And it happened on camera this week when he told reporters that he could have a “very, very good deal” to end the war with Iran in two or three days.

“You’ll be signing a peace agreement in two or three days?” a reporter asked, repeating Trump’s own words back to him.

“No, no, we have a good chance of doing it,” Trump said. “We should be able to do it in one hour, if you want to know the truth.”

Trump on Iran deal: Two or three days.. we have a very good chance of doing it. pic.twitter.com/t7MgG1ecA9

O’Donnell seized on those last seven words.

“Here’s a phrase I’ve never used: ‘If you want to know the truth,’” O’Donnell said, calling it a “weirder version” of the commonly used phrase “to tell you the truth.”

But Trump uses it a lot without thinking about what it means.

“The implication is the person saying that doesn’t always tell the truth,” O’Donnell said. “It’s one of Donald Trump’s tics: ‘If you want to know the truth.’ And every single time I have ever heard that man use that phrase ― ‘If you want to know the truth’ ― he’s said it after a lie.”

He noted that Trump’s “two or three days” claim is in contradiction to his comments last week that it “takes years” to make these kinds of agreements.

“And so, yes, we want to know the truth,” O’Donnell said. “And we all know it’s impossible to get that from Donald Trump about anything.”

O’Donnell pointed again to the clip of Trump this week saying he could have a deal in two or three days, only to walk that back when his own words were repeated.

“That’s what we’re dealing with in the presidency during wartime,” he said. “That’s the clown on the other side of the negotiations that Iran might or might not be engaging in with the United States.”

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