Zac Efron has teased he would like to return to his High School Musical roots.

The 26-year-old said he would reunite with his co-stars and reprise his role as singing basketball star Troy Bolton for a film sequel.

"We're all thinking about it. (I would) 100 per cent," he told E! News.

Zac, who was promoting his new film Neighbours at the SXSW festival, added: "I continue to see all the guys from High School. Every time we do... there's just this look between us. It's so cool because we never forget a single moment of that experience."

The High School Musical franchise, which propelled Zac to stardom and also starred Vanessa Hudgens, Ashley Tisdale and Corbin Bleu, started as a TV film on the Disney Channel in 2006.

A 2007 sequel and 2008 film followed, along with several spin-offs, a concert tour and a book series. It even spawned a stage musical, an ice tour and video games.

Zac, who has starred in films like The Paperboy, That Awkward Moment and Parkland since High School Musical ended, had a blast filming Neighbours alongside co-stars Seth Rogen, Christopher Mintz-Plasse and Craig Roberts.

"For us, we really had a fraternity," he said. "We really made it into a fraternity. It was kind of method. It really was. It was just so much fun."

The actor admitted he didn't mind shooting the raunchy bits either, saying: "It was neat. For me it was essentially the same as filming a drama. They took it really seriously."