Jessica "Extremely Happy" for Nick

Jessica Simpson is speaking out about her ex-husband's engagement -- and, according to her, she couldn't "be more happy."

In a new interview with Ryan Seacrest, Jessica says "I am extremely, extremely happy for him ... My mom actually called me and said that everyone was saying that I was 'saddened.' I was just in complete shock. I couldn't be more happy for Nick."

Jessica adds, "Our relationship was over a really long time ago, and it would be nice if everyone could move on with us and really just celebrate the love between him and Vanessa [Minnillo]. I do, and I really wish them nothing but the best"

Nick and Jessica were married from 2002-2006.