President Donald Trump has evolved on his demand for a ceasefire between Russia and Ukraine, and MSNBC host Nicolle Wallace thinks she knows why.

Wallace began with the Oval Office meeting on Monday between Trump and Ukrainian President Volodymyr Zelenskyy.

"Trump largely behaved himself. That counts as news," she said.

When it comes to the ceasefire, however, Trump has been all over the place since Friday.

"He did, though, either wittingly or unwittingly, make some news," Wallace continued. "It had to do with the necessity for a ceasefire between Ukraine and Russia. Listen to what Trump had to say on the topic throughout last week. And now something seemingly changed on that topic this afternoon."

She played several clips of Trump promising a ceasefire.

"It could be a good meeting, and we'll go a step further. We'll get it done," Trump promised on Aug. 11. "I'd like to see a ceasefire very, very quickly."

"I want to see a ceasefire rapidly," Trump said on Friday. "I don't know if it's going to be today. But I'm not going to be happy if it's not today."

"So, uh, we'll see what happens," Trump told Fox News, also on Friday. "I won't be happy without some form of a ceasefire."

But things changed Monday afternoon. Wallace remarked that it was after he met with Russian President Vladimir Putin.

"I don't think you need a ceasefire, you know? If you look at the deals that I settled this year, they were all at war, I didn't do any ceasefires," said Trump. "And, uh, I know that it might be good to have, but I can also understand strategically, well, one country or the other wouldn't want it. You have a ceasefire and they rebuild, and rebuild, and rebuild, and, you know. Maybe they don't want that. But if you look at the six deals that we made, peace and, you know, long-term, long-running wars, I didn't do any ceasefires."

Wallace said Russia doesn't want a ceasefire.

"So all of a sudden a ceasefire — I don't do ceasefires. We don't need those. Then, about an hour ago, Donald Trump shared this news on a key piece of any negotiations, security guarantees for Ukraine."

See the clip below or at the link here.

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