Elon Musk briefly joins Trump's call with Ukrainian President Volodymyr Zelenskyy

Tech mogul Elon Musk briefly joined President-elect Donald Trump's phone call with Ukrainian President Volodymyr Zelenskyy on Wednesday, according to a source familiar with the matter.

Musk, who campaigned for Trump in the final weeks of the 2024 race, was not scheduled to be on the call but walked into the room and greeted Zelenskyy, according to the source. He was not part of a substantive conversation between the two leaders, the person said.

Neither Zelenskyy nor Trump had previously disclosed that Musk was on the call. Axios first reported his participation, which was confirmed by other outlets.

Trump transition team officials declined requests for comment Friday. Neither Musk nor the Ukrainian Embassy in Washington, D.C., immediately responded to requests for comment.

Zelenskyy on Wednesday described his call with Trump as "excellent."

"We agreed to maintain close dialogue and advance our cooperation," Zelenskyy continued in a post on X. "Strong and unwavering U.S. leadership is vital for the world and for a just peace."

Trump has previously claimed that he could have the war "settled" in one day, asserting that if he is president-elect, "I’ll get it done before even becoming president." He did not lay out a plan for doing so.

During Trump's lone debate against Vice President Kamala Harris, Trump refused to say whether he wanted Ukraine, a U.S. ally, to win the war.

"I think it’s in the U.S. best interest to get this war finished and just get it done, alright," he said. "Negotiate a deal."

Vice President-elect JD Vance has also suggested that Ukraine should be ready to give up some of its territory to end the war.

Musk has also had phone conversations with Russian President Vladimir Putin, according to a source with knowledge of the matter. The conversations were first reported by The Wall Street Journal.

Near the start of the war, after Russia invaded, Musk helped provide internet support for Ukraine. Emergency Starlink receivers played a key role in helping Ukrainians communicate. Starlink systems are a service that is part of a SpaceX, which Musk owns.

But he has also angered Ukrainians for suggesting the country give up some of its territory to Russia. In October 2022, he suggested that Ukraine cede Crimea to Russia as part of a possible peace deal, drawing rebukes from Zelenskyy and other Ukrainian officials.

This story first appeared on NBCNews.com. More from NBC News:

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