Julia Roberts Was 'So Uncomfortable' Playing an Actress in Notting Hill: 'I Almost Didn't Take the Part'

Notting Hill could have featured a very different actress in the role of — well, the actress.

In a conversation with the 1999 romcom's screenwriter Richard Curtis for British Vogue's February issue, cover star Julia Roberts admitted that "one of the hardest things I’ve ever had to do" was play the lead role of Anna, an A-list star like Roberts herself.

"I was so uncomfortable!" Roberts, 56, told her longtime friend and colleague. "I mean, we’ve talked about this so many times, but I almost didn’t take the part because it just seemed — oh, it just seemed so awkward."

"I didn’t even know how to play that person," she added.

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Roberts also told Curtis, 67, that she "loathed" the clothes Anna was initially supposed to wear during the iconic scene where she tells Will (Hugh Grant), "I'm just a girl, standing in front of a boy, asking him to love her."

"My driver, lovely Tommy, I sent him back to my flat that morning. I said, 'Go into my bedroom and grab this, this and this out of my closet,' " Roberts recalled. "And it was my own flip-flops and my cute little blue velvet skirt and a T-shirt and my cardigan."

Directed by Roger Michell and written by Curtis, Notting Hill starred Roberts and Grant, 63, as Anna and Will, a movie star and a bookstore owner who embark on an unlikely romance filled with hurdles surrounding Anna's fame — but end up happily married with a baby on the way.

Of the "I'm just a girl ... " line becoming as famous as it did over the nearly 25 years since Notting Hill's release, Roberts said, "I mean, it was a great scene."

"But who knew that that would become the line," she added.

Curtis, who is also responsible for writing other other classic romantic comedies like Love Actually, Four Weddings and a Funeral and Bridget Jones's Diary, recently spoke with PEOPLE about his new Christmas movie Genie starring Melissa McCarthy.

At one point in the conversation, he said he "couldn't believe" he was able to nab McCarthy, 53, for the lead role, and that it reminded him of another time he was able to get exactly who he wanted — namely Roberts, for Notting Hill.

"I've actually got a photograph of me sitting in a chair receiving the phone call when Julia Roberts said yes to Notting Hill," said the filmmaker. "Because we'd offered it to her and we thought, 'That's never going to happen.' And it was a bit the same with Melissa."