Ukrainians are hailing first lady Melania Trump as an “undercover agent” in support of their cause, seeing her as instrumental in persuading her husband to break with President Putin and shift his stance on the war.

President Trump credits his wife for pointing out that Mr. Putin has repeatedly offered lip service about a cease-fire in Ukraine while pressing ahead with his relentless bombing campaign.

“I go home, I tell the first lady: ‘I spoke with Vladimir today. We had a wonderful conversation,'” Trump said to reporters in the Oval Office on Monday. “She said: ‘Really? Another city was just hit.'”

“We thought we had a deal numerous times. I get home, I’d say, ‘First Lady, I had the most wonderful talk with Vladimir. I think we’re finished,'” Mr. Trump said. “And then I’d turn on the television, or she’ll say to me one time, ‘Well, that’s strange because they just bombed a nursing home.'”

The president’s account sent ripples through Ukrainian social media. Shortly after his statements, a meme surfaced on X featuring a doctored photo of Mrs. Trump at her husband’s inauguration — her jacket now emblazoned with the Ukrainian Armed Forces logo — captioned, “Agent Melania Trumpenko.”

More pictures flooded social media, including one showing Mrs. Trump in combat fatigues, draped in the Ukrainian flag.

“Lots of love for Melania Trump on Ukrainian social media tonight,” a current affairs magazine, Business Ukraine, posted on X. An accompanying meme showed three cartoon characters presenting her with a Ukrainian military hat.

 “Melania singlehandedly doing more for Ukraine than the entire GOP,” one user replied.

After fruitless months of quiet diplomacy Mr. Trump issued an ultimatum to Mr. Putin on Monday, giving him 50 days to come to a peace agreement with the Ukrainians or face significant consequences, including new tariffs and sanctions.

“I’m disappointed in President Putin because I thought we would’ve had a deal two months ago, but it doesn’t seem to get there,” Mr. Trump said. “So, based on that, we’re gonna be doing secondary tariffs if we don’t have a deal in 50 days. It’s very simple.”