Donald Trump is searching for an "all-American" with a "central casting image" to be his Supreme Court nominee as he adopts an Apprentice-style approach to the task.

White House officials close to the US president say personality will be as important a factor as politics in the decision, a strategy Mr Trump has taken with previous high-profile appointments.

Mr Trump has chosen 9pm on Monday evening, a primetime TV slot, to make his announcement.

Adding to the theatre of the appointment, Mr Trump says he has narrowed his choice down to three candidates - but hinted not even all of his inner circle are aware of his choice yet.

Mr Trump is known to have held interviews with the three contenders this week - they are widely reported to be Amy Barrett, Brett Kavanaugh and Raymond Kethledge.

The opportunity to nominate a judge to sit on America's highest court opened up after Justice Anthony Kennedy - a key swing vote on landmark issues such as abortion and gay marriage rights - announced he would be stepping down at the age of 81.