NEW YORK • US President Donald Trump's Twitter outburst demanding to know why a university academic accusing his Supreme Court nominee of sexual assault in the 1980s failed to come forward sooner has spawned a new #MeToo era hashtag that has stormed the Web.

#WhyIDidntReport was the top trending conversation starter on Twitter in the US last Friday, as people - mostly women - vented outrage and stood in solidarity with Dr Christine Blasey Ford, the Californian professor who took decades to accuse Judge Brett Kavanaugh of groping her when they were teens.

By mid-afternoon East Coast time, tens of thousands of tweets had been posted to the microblogging platform as users explained why they had not reported occasions on which they, too, had been sexually assaulted in the past.

"I was sexually assaulted twice. Once when I was a teenager. I never filed a police report and it took me 30 years to tell my parents," tweeted actress Alyssa Milano.

Activist Ashley Judd, one of dozens of women who have accused disgraced film producer Harvey Weinstein of harassment, tweeted: "The first time it happened, I was seven. I told the first adults I came upon. They said 'Oh, he's a nice old man, that's not what he meant'. So when I was raped at 15, I only told my diary. When an adult read it, she accused me of having sex with an adult man."

Last Friday, Mr Trump abandoned any restraint over Dr Ford as he demanded that the Republican-controlled Senate get on with confirming Judge Kavanaugh.

"Why didn't someone call the FBI (Federal Bureau of Investigation) 36 years ago?" the President tweeted.

"I have no doubt that, if the attack on Dr Ford was as bad as she says, charges would have been immediately filed... by either her or her loving parents," he added.

AGENCE FRANCE-PRESSE