Salma was eager to celebrate Penelope’s big day and the images she posted on Instagram blew their fans away.
The Mexican-born actress shared two side-by-side images of herself and the Vanilla Sky star and they were as stunning as each other.
WATCH: Salma Hayek shares beauty secret behind her youthful appearance
Salma wore a white bikini and sheer cover-up which showed off her toned figure, while Penelope's crocheted, retro look was nothing short of stunning.
"Women in white," the Bliss star captioned the post. "Still celebrating the magnificent Penelope Cruz who had her birthday yesterday!!"
Her fans couldn't wait to comment and wrote: "2 of the most beautiful women of all time," and, "utterly stunning," with another adding, "they have such a wonderful friendship," and many more simply posted on-fire and heart emojis.
Salma wished Penelope a happy birthday with the throwback photos
The birthday girl turned 47 on 28 April and is just a few years younger than her friend, who will ring in her 55th birthday this year.
In 2013, Penelope revealed the fun nicknames they have when she told Allure: "We call each other huevos [eggs]. It was because when we were working together, we didn’t have children yet, so we used to sleep much more than now. So it was a way to call each other lazy."
Salma and Penelope have only starred in one movie together
While they have been friends for years, they've only made one film together.
Back in 2006, they starred in the bank-robbing movie, Bandidas. They've both since gone on to make a host of other films, but they are yet to be co-stars again.
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