Defiant Biden vows to stay in race after verbal gaffes at press conference

US President Joe Biden, who is facing intense scrutiny amid questions over his age, gave no indication he would consider dropping out of the electoral race in a press conference that lasted almost an hour on Thursday. He fielded tough questions from reporters about his mental acuity after he made two verbal slips, including mistakenly referring to his Vice-President Kamala Harris as "Vice-President Trump" and to Ukraine's leader Volodymyr Zelensky as "President Putin", triggering gasps in the room.