Incumbent US President Donald Trump said on Twitter that he believes that Pennsylvania votes were rigged. His tweet has been marked as "disputed" and potentially "misleading".
Earlier, the United States Court of Appeals for the Third Circuit in Philadelphia, Pennsylvania has struck down the Trump campaign's request to block Joe Biden from being certified the winner of the state, stating that the campaign failed to provide sufficient proof of its allegations.
On Thursday, Trump said that he would leave the White House if the Electoral College voted for Biden. He also stressed that it would be a mistake for the Electoral College to vote for Biden.
While the official results of the 3 November election have not yet been announced, all major US media outlets have called the race for Biden.
Trump has until 8 December to challenge and resolve election disagreements before the Electoral College meets on 14 December to formally declare the winner.