"She's really happy," a source tells the Insider. "It's going to be a great weekend."
Spears herself hinted at her engagement, which sources have been expecting for some time now, on Twitter Friday morning, writing: "OMG. Last night Jason surprised me with the one gift I've been waiting for. Can't wait to show you! SO SO SO excited!!!! Xxo."
The couple has been "talking about marriage for a long time," sources tell People.
Trawick reportedly popped the question to the pop superstar Thursday night, his 40th birthday, over a private romantic dinner.
Neil Lane confirmed to the Insider that he worked personally with Trawick to make Spears' dream ring. The engagement bling reportedly features a round stone that's over 3 carats and pave diamonds on the band.
According to Us Weekly, the spouses-to-be plan to celebrate their engagement tonight at Planet Hollywood in Las Vegas.
- Britney Spears