The British event planner's boyfriend, banker Nico Jackson, popped the question during their early December trip to India's Oberoi Amarvilas, insiders share. (Oberoi Amarvilas is a five-star resort, with views of the famed Taj Mahal.)
"It was exactly how he planned it," one source tells Us of the proposal. "Very romantic and grand!"
Together for 15 months, the couple were first rumored to be engaged back in September. Those rumors were false, but the two were clearly smitten. They even engaged in some PDA at the 50th anniversary party for Annabel's nightclub on Sept. 27.
Since the engagement, Middleton, 30, and Jackson, 36, have been celebrating their happy news in private. A source says they plan to spend Boxing Day (Dec. 26) at her family's Bucklebury estate before heading to the Alps for vacation in the new year.
Keep clicking to see photos of Pippa with Nico, her sister and more ...