Put on your brightly coloured skivvies and jump into the Big Red Car: the original line-up of the Wiggles has announced a rare reunion gig, in aid of bushfire relief.

The Wiggles revealed on Monday that they would get together for an over-18s show to take place in Sydney next week.

The original line-up of the Wiggles (from left): Anthony Field, Greg Page, Murray Cook and Jeff Fatt

"We’re getting the band back together ... to raise some much-needed funds to assist with those affected by the bushfires in Australia," the Wiggles said in a Facebook post.

"ALL proceeds from the show (tickets and merchandise sales) will be going to the Australian Red Cross and [wildlife rescue organisation] WIRES."