Kelly Osbourne has has said sorry for using an “offensive” slur during a recent magazine interview.

The reality star had used the word “tranny” to refer to Elle Schneider, who is awaiting gender reassignment surgery.

Osbourne’s ex-fiancé Luke Worrall had had a liaison with Schneider.

In 2010, Osbourne and her mother Sharon tackled anti-gay protesters at LA Pride.

Sharon shouted: “You should be ashamed of yourselves!”, while Kelly yelled: “My God loves gays!”

Reports said they then led gay revellers in drowning out noise from the protesters.

Kelly Osbourne has also been photographed for the NOH8 campaign, against California’s gay marriage ban.

In a letter to Gay and Lesbian Alliance Against Defamation coinciding with the International Transgender Day of Remembrance, Osbourne wrote:

I gained a lot of knowledge, and I now feel the urgency to speak out and teach others… As a lifelong LGBT ally and friend, I feel it is my duty to not only apologize for my wrong but to also correct it.

The word ‘tr*nny’ is a derogatory and hurtful word.

I was completely ignorant to this and soon came to realize most of my peers and Lgbt friends are, too.

This is a word I will no longer use or allow.

It wasn’t until I Googled it after speaking with GLAAD that I found out just how unbelievably offensive it was. When friends jokingly called me that in the past, I took it as a compliment or a joke, but I couldn’t have been more wrong.

Transgender people are some of the bravest people on Earth and among the LGBT community.

I cannot imagine the courage it takes to live your life openly and honestly, reflecting who you truly are, or the hurt that comes from having to hide who you are because others may not support and accept you.

Due to the fact that it is Transgender Day of Remembrance on 20 November, I would like to raise awareness of this injustice in society.

It is a day to remember those who have lost their lives due to anti-transgender violence and speak out against the fact that transgender people face disproportionate amounts of discrimination and harassment every day.

The lack of knowledge about transgender people contributes to the unparalleled numberof violent acts against them every day.