Steven Spielberg & Rachel Zegler Sing Rita Moreno 'Happy Birthday' on ‘West Side Story’ Red Carpet (Exclusive)

The 'West Side Story' actress was met with a cake while on the Hollywood premiere of the film, as she gears up to turn 90 this Friday.

Happy birthday, to Rita Moreno and Steven Spielberg! ET's Nischelle Turner was speaking to West Side Story director on the red carpet for the film's Hollywood premiere, when Moreno joined him and was met with a sweet birthday surprise from ET and the re-imagined classic's leading lady, Rachel Zegler.

After being presented a big, pink birthday cake, Spielberg, whose birthday is Dec. 18th and Moreno, who turns 90 on Friday, began singing the birthday tune when Zegler surprised the pair and joined in on the fun.

"Happy birthday to us," Moreno sings as she holds on to the cake. "Happy birthday to us. Happy birthday dear you and me, happy birthday to us."

Moreno gushed over Zegler, telling her, "You look like a princess!" Zegler responded in kind, calling Moreno "the queen."

"Ok, I'll be queen and you'll be the princess," Moreno added with a laugh and warm smile.

VALERIE MACON/AFP via Getty Images

Ahead of the little red carpet birthday celebration, Spielberg joked about the movie coming out just in time to be a celebration for Moreno's milestone birthday.

"I've said 90 is a publicity stunt. She's been planning her 90th birthday, but she's actually about 61," Spielberg said with a laugh. "And she dances like a 45 year old!"

Moreno -- who won an Oscar for her performance in the original 1961 film -- was effusive in her praise for the new take on the classic story.

"This is the best damn movie! It is the best," she said with glee. "I am so proud to be a part of this."

West Side Story is in theaters on Dec. 10.

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