US President Donald Trump has at last set the stage for leaving office in January by agreeing to work with Joe Biden on the transition to his presidency, even as he stubbornly asserted that he would ultimately win.

He tweeted on Monday evening that he was agreeing to cooperate with Biden in the "best interest of our country" for him to become the 46th President of a country facing a profound crisis brought on by the COVID-19 pandemic touching every aspect of life.