BACKSTREET Boys singer Brian Littrell sparks concern after his voice cracked and wobbled during a live performance.

The band appeared on the Today show to sing their smash-hit track, I Want It That Way.

Nick Carter, Howie Dorough, AJ McLean, Brian Littrell, and Kevin Richardson make up the members of the fan-favourite group.

Together, they have been active in the music industry for decades since their formation in 1993.

The band was welcomed into the studio of NBC‘s flagship breakfast television show for a live performance.

Savannah Guthrie, Craig Melvin, Carson Daly and Al Roker couldn’t help but get excited over the special guests.

This was to promote their nine-gig residency, “Into the Millennium,” at the Sphere in Vegas.

It will feature hits from their smash-hit 1999 album, Millennium, as well as other tracks from their long discography.

However, their promo did not go exactly as planned as Brian’s part did not feature his usual dulcet tones.

As he attempted to sing his solo, fans could not help but see how his voice appeared to crack.

The singer wobbled his way through his dedicated part, before Nick Carter took over the vocals.

Alongside the Valentines Day performance, the band also made another huge announcement.

To celebrate the 25th anniversary of their album, they are set to release Millennium 2.0 in July this year.

It has been over half a decade since the boys were last in Sin City, but their fans await their highly-anticipated return to the strip.

Over their career, the group have sold over 130 million records worldwide.

Apart from Led Zeppelin, they remain the only boy band to have their first ten albums to reach the top 10 in the Billboard 200 charts.