Move over, Leighton Meester!

Blake Lively has a new BFF on the Upper East Side: Anna Wintour, the notorious Vogue editor-in-chief who reportedly inspired the roman à clef The Devil Wears Prada!

The 23-year-old Gossip Girl actress -- who has appeared on the fashion mag's cover twice in two years -- opens up about her new friendship with the famed fashion editor in the October issue of Marie Claire UK.

"I was speaking with Anna Wintour and we were just talking about different fashion houses and I said, 'I love Chanel,' and she said, 'You should come with me to the show,'" Lively recalls. "I also said I loved Dior. She said, "Okay, well I'll take you to the Chanel and Dior shows and we'll meet with Karl [Lagerfeld] and John [Galliano] afterwards.' Insane!"

And Lively says she's learned a lot from sitting front row at Paris Fashion Week with the 60-year-old editor.

"I've always loved fashion. That's why I don't use a stylist," Lively tells the mag.  "It's such an expression of self."

Though she's happy to dish on her newfound friendship, Lively stays mum on her relationship with costar Penn Badgley, 23.

"At the end of the day, you're just in any relationship. How does anybody go to work every day and come home?" she asks. "You just do it and it either works or it doesn't."