There’s no denying that Julia Roberts is a big fan of a fashion uniform: when she's not wearing Calzedonia tights, an A-line skirt, cream silk shirt and pointed, formal black heels (as she is when we sit down with her), she favours a more androgynous style. It is this which drew her to her first favourite designer, Giorgio Armani.

“The first designer that I felt a kinship and a relationship with was Giorgio Armani, who is just a timeless and classic and incredible designer, and it’s because I'm so attracted to menswear that I was so attracted to him,” she tells us.

Nowadays, though, she places her faith in former Givenchy creative director Riccardo Tisci, whom she credits as being another designer who just gets her, and always gets it right.

“I’m not a great shopper,” says Roberts. “I have a great relationship with Riccardo Tisci, he understands me and what I like to wear...  yet he still gets me out of my comfort zone.”

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Fashion, clothes and costumes are incredibly important to actors, becoming an essential way of communicating characteristics of the role they’re playing. With this in mind, who does Roberts have pegged as her best and worst dressed characters of all time?

“I really couldn't say there was a worst,” she says tactfully, “but I recently saw a clip a of a movie where I wearing a very short t-shirt and I was shocked at myself.”

Roberts loves dressing-up, however, and she found her dream movie wardrobe on the set of Mona Lisa Smile. “Those were impeccable costumes,” she recalls, “and I was saying earlier about harking back to the days when people dressed up more – that was really fun.

“My husband actually threw me a beautiful surprise birthday party during the making of that movie, and everybody came dressed to the tee. All my girls from the movie came and they all looked so beautiful – and part of what was incredible about that party was how well-dressed everybody was, that we weren't all in jeans and a t-shirt.”

Roberts was recently voted the world's most beautiful woman for the fifth time by People magazine, and she says of the accolade: “It’s flattering, I don't really know [that] it’s anything more than that.

“I still look the same in the morning and then 38 people come with their sparkle and their masonry and help me look like this for you, which I’m incredibly grateful for.”

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Roberts turns 50 on 29 October this year. How is she feeling about reaching the milestone?

“I’m excited to turn 50, it really does just feel like a number – it sounds so cliché but the closer I get to 50 the more the clichés come true,” she tells us.

“I don’t think anyone is really panicking about getting older. It’s kind of this made up thing that we perpetuate in a way.”

Of course, living in LA as a well-travelled, global citizen with the current political situation must be difficult. When asked to reflect on the Trump administration, Roberts admits “Our country is not at its best right now, you have to not give up hope. This is the time you have to rise up as a community, and as a household, and as a country.

“My children are old enough to be aware of politics, so it's very important for my husband and myself to be honest with them, and make them feel like they still have a voice in the world for the things that they believe in.”

Amen to that.

Images: Rex Features