The incumbent president made the remarks at a campaign event in Macon, Georgia and now the video is being widely shared on Twitter.
"I shouldn't joke because you know what? Running against the worst candidate in the history of presidential politics puts pressure on me. Could you imagine if I lose? My whole life, what am I going to do? I'm going to say ‘I lost to the worst candidate in the history of politics'. I'm not going to feel so good", he said.
"Maybe I'll have to leave the country? I don't know." the President added.
Several supporters of Joe Biden took to Twitter and wrote "I’m Joe Biden and I approve this message" as humorous reaction.
The anti-Trump Republican group The Lincoln Project also posted the video of Trump and captioned it "Promise?"
Last month at a campaign rally in North Carolina, Trump had similarly said: "If I lose to him, I don't know what I'm going to do. I will never speak to you again".
This statement comes soon after reports of Donald Trump trailing behind Joe Biden in key states. As per new reports, Joe Biden's town hall on ABC News drew 14.1 million viewers, which more than the ratings for President Donald Trump's town hall on NBC News,
The data from Nielsen Media Research has revealed that Trump's event telecast across NBC and its sibling cable channels of MSNBC and CNBC in the same hour, drew 13.5 million viewers altogether.
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