Remember them? The Backstreet Boys look almost unrecognisable as they grab a bite to eat in Perth ahead of their Australian tour – as heartthrob AJ McLean puffs on a cigarette

American boy band The Backstreet Boys have touched down in Australia ahead of their tour.

Nick Carter, AJ McLean and Brian Littrell were spotted having dinner at a hotel in Perth on Thursday.

The trio looked almost unrecognisable as they grabbed a bite to eat and puffed away on cigarettes, keeping a low profile ahead of their string of shows, which begin on Saturday at the RAC Arena.

The Backstreet Boys, consisting of Nick, AJ, Brian, Howie Dorough and Kevin Richardson, are the biggest selling boy band of all time and have sold a whopping 100 million albums.

They are set to play in Perth on Saturday, before heading to Melbourne, Sydney and Queensland as part of their DNA World Tour.

The Backstreet Boys looked almost unrecognisable as they grabbed a bite to eat in Perth on Thursday ahead of their Australian tour. Brian Littrell is pictured

The Backstreet Boys, consisting of Nick, AJ, Brian, Howie Dorough and Kevin Richardson, are the biggest selling Boy Band of all time and have sold a whopping 100 million albums. They are pictured here in 1995

Samantha Jade will be their supporting act for the Australian shows.

Brian, 48, and Nick Carter, 43, kept a low profile and sported caps as they sat down together for their meal on Thursday.

AJ, 45, flashed his numerous tattoos in a navy T-shirt.

He also puffed away on a cigarette in an area away from diners, before returning to the table to finish his meal.

Brian, 48, and Nick Carter, 43, kept a low profile and sported caps as they sat down together for a meal

AJ, 45, puffed on a cigarette and flashed his numerous tattoos in a navy T-shirt

The boys kept a low profile ahead of their string of shows that begin on Saturday at the RAC Arena in Western Australia

The band first formed in Florida in 1993 and they last toured Australia in 2015

The band first formed in Florida in 1993 and they last toured Australia in 2015.

Last month, Nick Carter held a benefit concert in memory of his estranged late brother Aaron Carter and raised $150k for a children’s mental health charity.

Former child star Aaron was found dead in his bathtub at his Lancaster, California home on November 5 at age 34.

Last month, Nick held a benefit concert in memory of his estranged late brother Aaron Carter and raised $150k for a children's mental health charity

He was also joined by Backstreet Boy bandmate AJ, 98 Degrees' Jeff Timmons, O-Town and LFO for the concert reports TMZ - which saw him break down in tears onstage as he paid tribute to Aaron

Samantha Jade is set to be The Backstreet Boys' supporting act for the Australian shows

'See ya Down Under,' the group posted when they shared the news about their supporting act

Troubled former teen idol Aaron Carter was found dead aged 34 in the bathtub of his California home on November 5 - he and Nick were estranged at the time of his death (pictured 2004)

His fiancée Melanie Martin and mother Jane have recently claimed he died from an overdose and did not drown in his bath as previously suspected.

Nick was also joined by Backstreet Boy bandmate AJ, 98 Degrees’ Jeff Timmons, O-Town and LFO for the concert reports TMZ – which saw him break down in tears onstage as he paid tribute to Aaron.

He also performed a song penned in Aaron’s memory called Hurts to Love You.

Aaron, who rose to fame as a child star, battled mental health conditions including schizophrenia, bipolar disorder and manic depression, as well as substance abuse during his lifetime.

The group are soon set to play dates in Iceland, Egypt, India and the UAE

'We weren't kidding when we called it the DNA World Tour,' they wrote in one recent Instagram post