"Now I will admit coming here tonight wasn't the easiest thing for me," Mrs Clinton said in a speech at the annual gala of the Children's Defense Fund, the child advocacy organisation where she started her legal career.

"There have been a few times this past week when all I wanted to do was to curl up with a good book and never leave the house again."

Mrs Clinton did not mention Mr Trump once by name in the speech. She said in her concession speech last week that the country needed to give the billionaire businessman "a chance to lead".

"I know this isn't easy. I know that over the past week a lot of people have asked themselves whether America is the country we thought it was," she said.