Here's the real reason Trump and Zelenskyy's deal blew up in the Oval Office

According to sources close to Zelenskyy, tempers had flared even before the event began. The Ukrainian president was apparently presented with a minerals for security agreement by the Trump administration prior to the press event, but the deal included no security guarantees to protect Ukraine from another Russian invasion. 

Zelenskyy had warned repeatedly ahead of his trip to Washington, D.C., that, in order to reach a mineral agreement, Kyiv needed these security assurances. Even so, he angered Trump and Vance by rejecting the deal, the source said. 

TUNE IN: BRET BAIER INTERVIEWS ZELENSKYY ON 'SPECIAL REPORT,' 6 PM ET ON FOX NEWS

Subsequently, just minutes after reporters asked their first questions, an aggressive spat unfolded between the heads of state that left officials behind the scenes scrambling to understand how the situation fell apart so quickly. 

Zelenskyy's refusal to sign a deal apparently contributed to the ire of Trump and Vice President JD Vance.

The heated spat unfolded after Trump suggested Russian President Vladimir Putin invaded Ukraine in 2014 and again in 2022 because Trump wasn't in office, blaming Democratic presidents Barack Obama and Joe Biden, who sat in the Oval Office at the corresponding times.

"Yeah, that's exactly right," Vance said. 

Zelenskyy pointed out that Russia never stopped attacking Ukraine between 2014 and 2022, four years of which included Trump's first term. 

"Nobody stopped him you know," Zelenskyy said, adding that Putin repeatedly violated bilateral agreements. 

Vance interjected, saying, "I think it's disrespectful for you to come into the Oval Office to try to litigate this in front of the American media."

Zelenskyy has repeatedly pointed out that while the U.S. under the Biden administration approved substantial aid to Kyiv, it is Ukrainian soldiers fighting on the front lines to stop Russian aggression that poses a threat to all of Europe and could embolden adversaries like China, North Korea and Iran, which run counter to U.S. interests. 

"You have nice ocean and don't feel now, but you will feel it in the future," he argued. 

An angered Trump said, "Don't tell us what we're going to feel. We're trying to solve a problem. Don't tell us what we're going to feel."