The pop star Sam Smith has come out as non-binary and asked to be addressed by the pronouns they/them. Smith, 27, wrote on Instagram: “After a lifetime of being at war with my gender I’ve decided to embrace myself for who I am, inside and out.”

In an interview with Jameela Jamil published in March, Smith said: “I’m not male or female, I think I flow somewhere in between. It’s all on the spectrum.” Smith described being non-binary as “your own special creation”.

In their Instagram post, Smith said they were “at no stage just yet to eloquently speak at length about what it means to be non-binary” but that their intention was to be “visible and open”.

Smith pledged to answer questions that fans may have, and cited “activists and leaders of the non-binary/trans community” that had aided their understanding of gender identity, among them the actor Laverne Cox, model Munroe Bergdorf and the charities Stonewall, Glaad and Mermaids.

Smith said they were “scared shitless but feeling super free right now” and asked fans to be kind and to make an effort not to misgender them. “I hope you can see me like I see myself now,” they wrote.

Toryn Glavin, the trans engagement manager at Stonewall, told the BBC: “We’re delighted that Sam Smith feels able to speak openly about their gender identity, and their visibility will have a huge impact on many non-binary people.

“Sadly we know that it is still far too hard for people to be open and accepted for who they are, and we will keep campaigning until every LGBT person is accepted without exception.”