Kate Hudson and Matt Bellamy

Kate Hudson and Matt Bellamy

Kate Hudson and Matt Bellamy appear to be "extremely happy" in Aspen, Colorado.

The former couple, who recently confirmed their split after four years together, proved they are still on amicable terms by doing some last-minute Christmas shopping on Monday evening (22.12.14).

An eyewitness said: "They were extremely happy, just really friendly."

The Muse rocker, who has three-year-old son Bingham with the actress, was also very chivalrous during their outing.

The insider told PEOPLE.com: "They stayed together. He carried her bags for her. They were laughing and smiling together."

The British musician, 36, recently insisted he and Kate, 35, were both "very happy" despite ending their engagement.

He said: "We're both very happy, it's for the best."

The 'Something Borrowed' actress, who also has 10-year-old son Ryder with her ex-husband, Chris Robinson, is rumoured to have already moved on from Matt with 'Dancing With the Stars' performer Derek Hough, who started giving her dance lessons last year.

The pair surprised everyone when they "acted like a couple" at a party in Los Angeles on December 5.

A source previously said: "As Kate told Derek about her problems with Matt, they grew closer and closer. Derek knew the relationship was over, so he didn't think twice about hooking up with Kate."