FIRST PIC: See Britney’s Stunning Engagement Ring!

Britney Spears

and her fiancé Jason Trawick made their debut as an engaged couple at Planet Hollywood in Las Vegas on Friday evening.

The pair, who originally planned to be in the city to celebrate Trawick's 40th birthday, made it a double celebration after getting engaged the night before. Us Weekly broke the news.

Meet Britney's fiancé Jason Trawick

Spears wore a pale pink dress as she proudly showed off the three carat Neil Lane sparkler given to her by her former agent beau.

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"This is something they've both wanted for a long time," a source explains to Us. "It's a way to cement their family. They're both extremely happy and can't wait to become man and wife."

PHOTOS: Inside their romance.