“We have to tend to this garden of democracy or else things could fall apart quickly,” Mr Obama said.
He went on to compare the situation to Germany in the 1930s where, despite a long history of high-level cultural and scientific achievements (and the existence of a functioning democracy), Adolph Hitler nonetheless rose to power, reported Crain’s Chicago Business.
“Sixty million people died,” he added. “So, you've got to pay attention. And vote.”
Although Mr Obama did not mention Donald Trump by name, some believed his comments were aimed at the current US president and his “Make America Great Again” rhetoric - which critics argue has fuelled nationalism.
Mr Trump has been accused of fuelling anti-Muslim sentiment across the US.
In November, the President came under fire for retweeting inflammatory videos from the Twitter account of a British far-right, ultra-nationalist figure, which contained anti-Muslim content.
His actions were publicly rebuked by prime minister Theresa May, whose official spokesperson condemned the president's actions as "wrong".
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