Natalie Portman says Reese Witherspoon helped her join Instagram

“Annihilation” star Natalie Portman laughingly acknowledged Monday that friend and fellow actress Reese Witherspoon was responsible for Portman having a social media account for the first time.

“Reese has been a wonderful support system in teaching me the ways of modernity: ‘There’s this thing called social media. You should check it out,’” Portman, 36, told Nischelle Turner of “Entertainment Tonight.” The interviewer had noted a cellphone video of Witherspoon -- with Portman in a Time’s Up T-shirt laughing along in the background -- saying, “She found out it’s 2018 and she joined Instagram!”

When Turner asked playfully whether Portman was concerned about becoming obsessed with Instagram, the Academy Award-winner -- born in Jerusalem, Israel, but raised primarily in Jericho, graduating from Syosset High School in 1999 -- laughed and replied, “I don’t know! It’s a very new thing in my life, and I feel like a grandmother who’s learned how to use the microwave. ‘Wow, it heats things up! This is amazing!’”

On Jan. 6, “A Wrinkle in Time” star and fellow Oscar-winner Witherspoon, 41, had posted an Instagram photo of herself and Portman in gowns, writing, “This is a photo of me convincing @natalieportman to join @Instagram!! Welcome her to the Insta family, y’all!”

Portman initially used an Instagram account titled “nportmanofficial,” starting with three posts on New Year’s Day that supported the Time’s Up initiative and defense fund for victims of sexual harassment and abuse. In one of three similar posts the next day, she wrote, “It’s time to shift the balance in the workplace, from representing the few to representing us all. #TIMESUP @TIMESUPNOW.”

She posted her first image of herself, a two-second video clip posing with actress Eva Longoria in Time’s Up shirts, on Jan. 6.

Portman quickly closed that account and moved the images to a new one, “natalieportman.” Her first post unrelated to the Time’s Up movement came on Jan. 27, a photo of herself on a movie set “directing my first feature, A Tale of Love and Darkness, in Jerusalem with my fierce first AD [assistant director], Shir Shoshani #femalefilmmakerfriday.”

Portman does not have a Twitter or Facebook account.