David Arquette: I can relate to Bruce’s transition

David Arquette says Bruce Jenner’s reported transition into a woman must be “really difficult for everyone”.

The 43-year-old actor can relate to the reality star’s situation as his sister Alexis was formerly his brother Robert.

But David told Access Hollywood Live on Wednesday he imagines that undergoing such a life change in the spotlight must be tough for Bruce and his family.

"It's such a personal thing, especially being in the spotlight. It must be really difficult for everyone," David said.

"He seems like a really sweet guy, girl. To be honest with you, that little faux pas that happened, is one of the hardest parts, to call my brother my sister now… but whatever makes them comfortable."

Alexis’ transition was documented in Alexis Arquette: She's My Brother, which showed at the Tribeca Film Festival in 2007.

She has since had success as an actress, with roles in movies such as Pulp Fiction and The Wedding Singer.

And David says he is thrilled that the world has become so accepting of the transgender community.

"I like the new age of our society, where we're more accepting and understanding of diversity and it just makes our world more colourful,” he said. “As long as you’re not a terrible person, hurting people, more power to you.”

Bruce is set to discuss his alleged transition in depth during an interview with Diane Sawyer, to be broadcast in the US on Friday.

Meanwhile, the 65-year-old star’s former high school sweetheart has come forward to reveal she was just as stunned as everyone else to hear of Bruce’s alleged lifestyle choice.

“I would have never though that in a million years [thought he would transition],” Michelle Rosenthal told Inside Edition.

“When it came out in the paper that he was thinking of this, I think everyone was really shocked.”