Jessica Simpson is "extremely happy" for her ex-husband, Nick Lachey's, new engagement.

The US singer and actress wishes her ex-husband all the best after TV host Vanessa Minnillo accepted his proposal last week.

She told host Ryan Seacrest on his KIIS-FM radio show: "I am extremely, extremely happy for him. I couldn't be more happy for Nick."

Jessica, 30, also dismissed reports she was "saddened" when she initially heard the news of Nick's proposal.

She continued: "I don't know where all those rumours came from. My mom actually called me and told me that everybody was saying I was 'saddened.' And I was just in complete shock."

Jessica was married to Nick, 37, from 2002 to 2006, and together they starred in four series of reality TV show 'Newlyweds: Nick and Jessica'.

Nick started dating Vanessa a few months after separating from Jessica - who is now dating NFL player Eric Johnson - and she added she is keen for the public to move on from their marriage.

She said: "You know, our relationship was over a really long time ago, so it would be nice if everybody could move on with us and really just celebrate the love between him and Vanessa. I do, and I wish them nothing but the best."