Duff and ex 'besties'

Hilary Duff and Mike Comrie. Picture: Getty Images

Despite recently dropping a bombshell on fans with news of their shock split, Hilary Duff has insisted husband Mike Comrie is still her "best friend".

The singer and actress only confirmed on Friday she had separated from the former ice hockey star, both above, after less than four years of marriage, but the two look to be quickly finalising the details of their split in the most amicable way possible.

Duff's mother has confirmed the pair will share joint custody of their 21-month-old son Luca Cruz, and hinted they were preparing to file for divorce sooner rather than later.

"They're better as friends than a married couple," Susan Duff told TMZ.com.

Duff, 26, and Comrie, 33, began dating in 2007 and later tied the knot in a lavish ceremony in California in 2010.

There had been no reports of trouble between the duo when a representative for Duff announced they had "mutually decided upon an amicable separation".

"They remain best friends and will continue to be in each other's lives. They are dedicated to loving and parenting their amazing son, and ask for privacy," the representative said.

The former Disney star thanked her fans for their well wishes on Twitter, writing: "Mike and I are sitting here, we are so appreciative for all of your kindness & well wishes. Not an easy day but we're getting thru it together."

A source close to Duff echoed the duo's comments, revealing they are still on good terms and simply grew apart. "There was no major incident - no big event between the two of them. They really did drift apart. They tried couples therapy, but in the end, they realised at this time, they work better as friends. And they really are great friends," the insider said.