Fergie and Josh Duhamel have split up.

The 'You Already Know' singer and the 44-year-old actor have revealed they went their separate ways earlier this year, but kept the news private for some time in order to ''adjust'' to the situation.

And the pair - who started dating in September 2004 and married in January 2009 - have vowed to remain ''united'' to support their four-year-old son Axl.

They said in a statement: ''With absolute love and respect, we decided to separate as a couple earlier this year.

''To give our family the best opportunity to adjust, we wanted to keep this a private matter before sharing it with the public. We are and will always be united in our support of each other and our family.''

The former couple haven't been seen together for some time, so it is unclear when they split, but they did celebrate their wedding anniversary together in January.

At the time, the 'Transformers' actor shared a family photo on Instagram and wrote: ''8 years!! Love you babe (sic)''

The news comes less than a week after Fergie, 42, laughed off speculation she and Josh were expecting their second child together.

She said: ''I've heard so many rumors about all of that. I have no idea what's in the future.''

Instead, the singer is focused on the release of her upcoming solo album, 'Double Dutchess', and admitted making the record has felt like she is ''birthing'' another child.

She said: ''I just turned all my videos in yesterday to everybody.

''It's like I'm birthing a different kind of baby. I feel like I'm birthing this thing out. It didn't come from my belly, but it came from my soul.''