Donald Trump has said he will leave the White House if Joe Biden is formally confirmed as the next US president.
Answering reporters’ questions for the first time since losing the 3 November vote, Mr Trump insisted, however, that “this race is far from over”.
He has refused to concede, citing unsubstantiated claims of voter fraud.
Individual states are currently certifying their results, after Mr Biden was projected as the winner with an unassailable lead.
The Democrat leads Mr Trump 306 votes to 232 under the electoral college system that is used to pick US presidents.
The tally is far more than the 270 needed to win, and Mr Biden also leads the popular vote by more than six million.
Electors will meet to formalise the result on 14 December, with Mr Biden due to be sworn in as president on 20 January.