Natalie Portman addresses her experience of 'sexual terrorism' at age of 13 at Women's March

Natalie Portman has said the ordeal of enduring “sexual terrorism” when she was just 13 years old forced her to give up a number of acting roles.

The Oscar-winning actor opened up about her distressing experience during a speech in front of thousands gathered in downtown Los Angeles for the Women’s March.

The event took place alongside similar events across the US this weekend which mark the first anniversary of the Women’s March against Donald Trump, who has a track record of making demeaning, sexist comments about women.

After the US President’s inauguration a year ago, activists took to the streets in 60 countries and on seven continents to promote equal rights for women and defend marginalised women.

Ms Portman, now 36, used her speech at the march to recall the experience of turning 12 on the set of 1994 film Leon: The Professional, where she gained her first role.

After the film was released, Ms Portman said she was excited about getting her first piece of fan mail but instead wound up reading a “rape fantasy that a man had written me”.

Ms Portman said: “A countdown was started on my local radio show to my 18th birthday – euphemistically the date that I would be legal to sleep with.

“Movie reviewers talked about my budding breasts in reviews. I understood very quickly, even as a 13-year-old, that if I were to express myself sexually I would feel unsafe and that men would feel entitled to discuss and objectify my body to my great discomfort.”

Ms Portman explained it forced her to change her behaviour, cast off roles which had kissing scenes and instead accentuate the “bookish and serious” element of her character. The actor carved out a reputation as a “prudish, conservative, nerdy, serious” young woman in the attempt to ensure her body felt protected and her voice listened to.

“At 13 years old, the message from our culture was clear to me. I felt the need to cover my body and to inhibit my expression and my work in order to send my own message to the world that I’m someone worthy of safety and respect,” she said.

“The response to my expression, from small comments about my body to more threatening deliberate statements, served to control my behaviour through an environment of sexual terrorism.”

Ms Portman applauded the marchers who attended the protest as she opened the event while Eva Longoria and Constance Wu stood by her side.

“You told the world that time’s up on violence,” she said. “You told the world that time’s up on silence. You told the world that it’s time for a new day, time for a new locker room culture and time to think about every person’s desires and needs, wants and pleasure.”

Hundreds of thousands of Los Angeles residents descended on to their city’s streets in what was said to be the largest of the Women’s Marches staged across the US.

The event also included a speech by fellow actor Scarlett Johansson who discussed how empowered she felt by “the brightness of this movement, the strength and the unity that this movement has provided. It gives me hope that we are moving toward a place where our sense of equality can truly come from within ourselves.”

Thousands of protesters poured onto cities across the US and beyond to call for equal rights for women and condemn misogyny and racism. Activists gathered in everywhere from Washington DC to Chicago, London and Japan.

Even Palm Beach, Florida, home to Mr Trump’s Mar-a-Lago estate, saw several hundred people assemble bearing anti-Trump placards.