President Barack Obama has said “I’d invite Mr Trump to stop whining and go try to make his case to get votes.”
The President tore into the Republican nominee following his continued claims that November’s US election is rigged.
“There is no evidence that that has happened in the past or that there are instances in which that will happen this time,” the President said.
“If you start whining before the game’s even over; if whenever things are going badly for you and you lose, you start blaming somebody else, then you don’t have what it takes to be in this job,” Mr Obama said during a press conference at the White House.
He called Mr Trump’s intensifying warnings about voter fraud “unprecedented” in modern politics, saying his claims were not based on evidence, but simply aimed at discrediting the election.
Mr Obama’s remarks came as Mr Trump and his Republican allies look for ways to swing momentum their way after a damaging few weeks in which his campaign has been rocked by allegations of sexual assault.
Mr Trump has denied the claims, saying they are “outright lies”.