U.S. President Donald Trump said on Thursday that he will leave the White House when the electoral college votes for Democratic president-elect Joe Biden, the closest the outgoing president has come to conceding defeat. The electors will cast their votes on December 14, formalizing the election outcome. Reporter: "So, if the electoral college does elect President-elect Joe Biden, are you not going to leave this building?" Trump: "Certainly I will and you know that, but I think there will be a lot of things happening between now and January 20." President-elect Joe Biden won the November election with 306 electoral college votes, well over the 270 required, to Trump's 232. Biden also leads Trump by more than 6 million in the popular vote tally. Trump has so far refused to concede defeat, but instead continues to make baseless claims about alleged voter fraud. He's launched legal attempts to challenge the outcomes in several states such as Pennsylvania and Michigan. Some of these have already been thrown out by the courts. "We know there was massive fraud," said Trump. After the traditional President's Thanksgiving Day address to U.S. service members, Trump told White House reporters it would be a 'very hard thing to concede' and declined to say whether he would attend Biden's inauguration, due for January 20. Earlier this week, the General Services Administration, or the agency that greenlights presidential transitions, told Biden he could formally begin the hand-over process, indicating Trump's possible readiness to move forward with procedure. However, Trump's refusal to officially concede the election could disrupt efforts by Biden and Vice-President elect Kamala Harris to tackle the escalating health crisis. After the electoral college casts their votes Congress will count the official tally on January 6.