Helen Mirren says it's "flattering" to be mistaken for Keanu Reeves' girlfriend — but no, she's not dating him

When Keanu Reeves confirmed his relationship with artist Alexandra Grant on Saturday, the Twitter world went into a tizzy. Who exactly is the heartthrob's new girlfriend?

One thing is for sure, she's not Helen Mirren — even though many people couldn't help but notice a striking resemblance between Grant and the famous actress.

Grant, 46, has silver hair like Mirren, and during her first public outing with Reeves, she wore her hair in a similar style to the 74-year-old actress.

Many people did a double take, assuming Reeves was arm and arm with Mirren on the red carpet at the LACMA Art + Film Gala. His date was, in fact, not the iconic actress, but she did catch wind of the relationship rumors.

"I saw that," Mirren told Entertainment Tonight on Wednesday after many people on social media mistook Grant for Mirren. "That was very flattering on me, you know, because she's obviously lovely."

Mirren spoke to ET while walking the red carpet for the New York premiere of her new movie "The Good Liar." Her co-star, Ian McKellen, was by her side — not Reeves.

Mirren is actually in her own relationship — she's been married to director Taylor Hackford for 22 years. Reeves, who is 19 years her junior, is no stranger to her and her husband.

"I do know Keanu very well," Mirren told ET. "He did a film with my husband and he is just the most adorable, lovely person. So, she's a lucky girl and I'm sure that he's a lucky boy." Reeves starred in Hackford's 1997 horror thriller "The Devil's Advocate."

While Reeves and Grant just recently stepped out as a couple, they have worked together for years. In 2001, she worked with him on his adult picture book, "Ode to Happiness," ET reports.

Grant and Reeves also collaborated on a book in 2016, later starting a publishing company together, according to ET.