Ashlee Simpson celebrates engagement

Ashlee Simpson has had an "amazing" engagement party.

In January it was revealed that the singer would be marrying musician-and-actor Evan Ross.

They've now had a pre-wedding celebration with their closest friends and family.

"What an amazing engagement party with all of our loved ones! We gettin' married :) (sic)" the star excitedly posted on Twitter.

The 29-year-old attached a picture of herself in a feathered headband gazing adoringly at 25-year-old Evan, who was wearing a white shirt and a furry coat.

Also in attendance was her older sister Jessica, 33, who is engaged to Eric Johnson.

"Celebrating my best friend and sister missbananahammock @ashleesimpson. I love her so much! (sic)" Jessica wrote on Instagram.

She also added a snap of herself with Ashlee, looking extremely slim in a cream mini dress with silver detail.

The blonde star has lost all the baby weight she put on while pregnant with her children with Eric, Maxwell and Ace.

Evan announced he was marrying Ashlee on his Twitter page in January.

The son of Diana Ross posted a picture of himself with his blonde fiancée gazing into the camera and showing off a sparkler on her ring finger.

"The love of my life said YES!!!!!! (sic)" he captioned the photo.

It will be the second marriage for Ashlee, who married Fall Out Boy star Pete Wentz in 2008.

They welcomed son Bronx the same year, but their divorce was finalised in 2011.

It's the first marriage for Evan.